Monday, June 29, 2020

Significant data improvement made to ANS Greek department

Last week, as I begin to transition from the basically-completed Hellenistic Royal Coinages project to publishing the Roman Republican Die Project, I took a few hours to dump a list of names that appear as authorities in the ANS's Greek department and reconcile them against Nomisma.org's API in OpenRefine.

Of the roughly 1,000 names that appear in the Authority facet, about 600 were successfully linked to Nomisma URIs, the majority of which were generated several months ago as a precursor to the launch of the new and improved Coin Hoards database. Of the remaining 400, a relatively small number (several dozen) are names that require further disambiguation between more than one entity (multiple Cotys or Mithridates are represented in the ANS collection) or rulers that have not yet been created in Nomisma. A larger portion of the remaining 400 are Roman magistrates that will be normalized at a later date as we begin to incorporate Roman Provincial Coinage Online URIs into our database or Celtic kings or tribes that will be created in Nomisma in the near future.

The linking of authorities in MANTIS to Nomisma results in a huge improvement in the usability of our Greek coinage. This not only improves that standardization of preferred labels (since we had previously implemented variant names and spellings for the same person in the underlying FileMaker curatorial database), but Nomisma also facilitates the indexing of related dynasty and corporate entity concepts into MANTIS. The Dynasty facet on the browse page is much improved (although not thoroughly cleaned, since we did not eliminate values from this facet for coins not linked to authorities).

Parthian coins in MANTIS


More importantly, the State facet now lists all of the overarching corporate entities linked to each individual ruler, satrap, magistrate, etc. This means that for the first time, it is possible to execute a simple query to gather all 1,600 coins of the Parthian Empire, 349 coins of the Kingdom of Elymais, etc. in one result set, rather than relying on the previous dynasty field, which was inconsistently cataloged.

Some further statistics:
  • Of the 94,723 coins in the Greek department, 38,563 are linked to Nomisma URIs for authority.
  • 32,177 coins are linked to a Nomisma concept for the related corporate entity. There are 84 corporate entities in total.

There is still much to improve here, both within the Greek department and beyond it, but this is a clear demonstration of the enhancements that can be made in usability by more thorough integration of Linked Open Data identifiers. The effort to achieve this was minimal (since most of the Nomisma IDs had already been created), but is a foundation on which we can build toward better data quality within other departments as we begin to transition from FileMaker to CollectiveAccess as our collections management system.

Friday, June 19, 2020

Hellenistic Royal Coinages union monogram catalog enabled

After making some minor updates to the XQuery that underlies the symbol pages in Numishare, I have enabled the unified monogram interface in the Hellenistic Royal Coinages umbrella site. There are now 2,800 monogram URIs in this interface spread across Seleucid, Ptolemaic, and Argead coinage, including posthumous issues in the name of Alexander the Great published in the PELLA project. These monograms can be filtered by constituent letter, as in individual projects, showing overlap between the various Hellenistic kingdoms. It will become apparent that identical monograms will have different URIs in the different type corpora. This will be addressed eventually, as we combine these images with monograms from other Greek numismatic projects, such as Corpus Nummorum, and issue unique URIs for each monogram concept in the Nomisma.org namespace.

Hellenistic monograms consisting of Χ and Ψ

Some minor updates to Numishare were made this morning to index the constituent letters from these monograms into a Solr facet that appears under the symbols section of the browse page in each project, as well as the HRC umbrella site. The letters are indexed at the level of obverse and reverse, but not specific positions, like other symbols. The Javascript that forms the Lucene query has been updated to replace the default operator from OR to AND for letters, since it is more useful to search for types related to all of the associated letters than any of them (in contrast to mints, denominations, etc., where a coin type is typically only associated with one).

Hellenistic coins with monograms that contain Χ and Ψ

Price 874
What interesting here is that there are two pairs of identical monograms in the results. One coin from each pair is from PELLA and the other from SCO. For example, Price 874 is the same monogram as Houghton 570.4. Looking at the types associated with these monograms, Price attributes one type (P151) to Philip III Arrhidaeus from Aradus, but the monogram appears on several Seleucid types. In particular, P151 appears to be identical to http://numismatics.org/sco/id/sc.1.Ad43.9, which also includes an identical monogram form (also with two different URIs in PELLA and SCO) in the left field (according to the images, but not the cataloging). The cataloging in PELLA is wrong here and should be fixed. The photographs associated with the Price type clearly show these monograms in left field, and Price 399 beneath the throne (perhaps wrongly encoded as the Greek zeta in SCO).

Price P151 and SC Ad43.9 have not previously been linked together as the same type. Four coins from the Ashmolean and BnF link to the Price URI, but no coins have been cataloged to the SC number. By inserting these types into our concordance list, we will be able to display the images for the coins in SCO. Furthermore, Houghton, Lorber, and Hoover attribute this type to Seleucus, minted in Babylon. While we will not change Price's cataloging to change the authority and mint for the type, ideally we want to to use the SC data as the canonical reference.

Thursday, June 18, 2020

About 1,300 Seleucid Monograms published to SCO

About 1,300 monograms appearing on the coinage of Seleucus I through Antiochus III (Houghton, Lorber, and Hoover's Seleucid Coins, Part 1) have been published to Seleucid Coins Online (SCO) and linked to thousands of types and subtypes. Much like previous work with PELLA and PCO, the constituent letters have been annotated by Peter van Alfen, although I am sure we will spot some errors or oversights in the process.

Where the SCO monograms differ from the previous projects is that monograms have been organized hierarchically by Oliver Hoover. Unlike in PELLA and PCO, where a monogram usually has one SVG file (but may have more than one to illustrate slight variations in style), the Seleucid monograms have been grouped thematically by letters and general design motif.

SCO monogram 299


For example Monogram 299 generally consists of Μ, Ε, and Υ, and has four sub-monograms linked to the parent through skos:broader in the RDF. These sub-monograms URIs (e.g, http://numismatics.org/sco/symbol/monogram.houghton.299_3), are encoded within the coin type data, which makes it possible to visualize the mints, hoards, and coin types connected at the sub-monogram level as well as the parent level, by extending the underlying SPARQL query all types associated with the parent monogram through each of the children:



  BIND (<http://numismatics.org/sco/symbol/monogram.houghton.299> as ?symbol)
  {
    SELECT ?symbol ?side WHERE {
     {?side nmo:hasControlmark ?symbol}
     UNION {?children skos:broader+ ?symbol .
              ?side nmo:hasControlmark ?children}
    }
  }


Similarly, Seleucid Coins is an extensively hierarchical type corpus. Many symbols and monograms are annotated at the subtype level. While individual subtypes are indexed into Solr in Numishare for OpenRefine reconciliation and the Atom feed (which powers lookups in KENOM), the browse page itself shows only parent types. The underlying code in Numishare was updated so that symbols and monograms annotated within subtypes are indexed into Solr, making it possible to access them from the symbol facets, regardless of whether that particular monogram appears explicitly within the data for the parent type. For example, Monogram 426 appears in SC 42.2, but has been indexed into the data for SC 42 so that it still appears on the browse page for the query, with two other non-hierarchical types in which the monogram appears directly. Coincidentally, Monogram 426 only appears on posthumous Alexanders minted in Carrhae from 310-290 B.C.

Query results for Monogram 426



Some technical advances I would like to implement in these user interfaces in the near future:

  • A histogram showing the dates of production for monograms
  • Plugging the monograms into the existing distribution analyses functions in Numishare and Nomisma (to generate charts showing authorities, mints, etc. that produced monograms)
  • Vary the radius of the mint points on the map by density of production
  • Introduce a draggable timeline into the map so that the geographic distribution can be visualized over time

The links between letters, monograms, types, mints (and other typological attributes), and hoards will open the door to completely new types of query that were not possible before the application of Linked Open Data to numismatics. We are barely scratching the surface of what's possible. I have recently queried a list of concordances between Ptolemaic monograms and mints from the Nomisma.org SPARQL endpoint that I plan to import into a network visualization tool, like Gephi, for experimentation.

Friday, June 12, 2020

Ptolemaic Monograms Published to PCO

More than 300 monograms pertaining to the coinage of Ptolemy I - IV have been published to Ptolemaic Coins Online. Like the functionality detailed in our publication of monograms in PELLA, the monogram images will appear in the browse and coin type pages, and the landing pages for monograms, e.g., Lorber 265, will show related coin types and a map of associated mints and findspots. Since the American Numismatic Society's collection pulls typological directly from PCO, the monograms will now appear directly in Mantis.



Unlike in PELLA, where more than one monogram does not often occur in the same position on a side of the coin, the combination of monograms, letters, and other symbols may appear together, sometimes in a particular horizontal or vertical alignment.

CPE 1.1 645, for example, includes two monograms arranged vertically in the left field, and lambda over another monogram in the right.

ANS 1944.100.76207 - CPE 1.1 645

In order to handle these particular placements, as well as choices between monograms (a type may include slight variations of a monogram), we have turned to using EpiDoc TEI for more granular annotation. EpiDoc was introduced in 2017 to facilitate increased granularity for legends, descriptions, and bibliographic references. I have recently updated the NUDS XML schema to allow for the namespacing of EpiDoc into the <symbol> element to differentiate between monogram URIs and tei:segs for letters. Many other symbols that appear on coins (e.g., dolphin, torch, lightning bolt, etc.) are still encoded as segs, but we will eventually replace these with URIs representing visual concepts.

The arrangement of symbols above is represented in TEI as:

<symbol position="leftField">
    <tei:div type="edition">
        <tei:ab rend="above">
            <tei:ab>
                <tei:am>
                    <tei:g type="nmo:Monogram" 
    ref="http://numismatics.org/pco/symbol/monogram.lorber.206"
    >Lorber Monogram 206</tei:g>
                </tei:am>
            </tei:ab>
        </tei:ab>
        <tei:ab rend="below">
            <tei:ab>
                <tei:am>
                    <tei:g type="nmo:Monogram" 
    ref="http://numismatics.org/pco/symbol/monogram.lorber.265"
    >Lorber Monogram 265</tei:g>
                </tei:am>
            </tei:ab>
        </tei:ab>
    </tei:div>
</symbol>
<symbol position="rightField">
    <tei:div type="edition">
        <tei:ab rend="above">
            <tei:ab>Λ</tei:ab>
        </tei:ab>
        <tei:ab rend="below">
            <tei:ab>
                <tei:am>
                    <tei:g type="nmo:Monogram" 
    ref="http://numismatics.org/pco/symbol/monogram.lorber.104"
    >Lorber Monogram 104</tei:g>
                </tei:am>
            </tei:ab>
        </tei:ab>
    </tei:div>
</symbol>

The @rend element is used in the <ab> or <seg> for particular renderings, e.g., to annotation rotation.

B544 is an illustration of a choice between two monograms, a variation of sigma that is facing either direction.


<symbol position="exergue">
    <tei:div type="edition">
        <tei:choice>
            <tei:am>
                <tei:g type="nmo:Monogram" 
    ref="http://numismatics.org/pco/symbol/monogram.lorber.250"
    >Lorber Monogram 250</tei:g>
            </tei:am>
            <tei:am>
                <tei:g type="nmo:Monogram" 
ref="http://numismatics.org/pco/symbol/monogram.lorber.118"
>Lorber Monogram 118</tei:g>
            </tei:am>
        </tei:choice>
    </tei:div>
</symbol>

These data are entered into spreadsheet columns following a particular standard, which the CSV-to-NUDS PHP script will parse into TEI XML. The same logic has been applied to the script for publishing Seleucid monograms. So expect to see those online in the year future.

Wednesday, June 3, 2020

Richard Abdy's new Hadrianic RIC volume published to OCRE

After a tremendous amount of work by ANS curatorial assistant, Lauren Tomanelli, and with the permission of Spink & Son and British Museum curator and author of the newest edition of Roman Imperial Coinage (Volume II, Part 3, second edition), Richard Abdy, the new coin types of Hadrian have been published to Online Coins of the Roman Empire.

The new volume includes more than 3,000 types of Hadrian, with a much more granular description of busts, we have taken a type/subtype approach to the new volume in order to minimize the reduction of physical specimens that are attributed to these types.

For example, RIC II.3 Hadrian 4-6 have three distinct busts:

  • Bust of Hadrian, laureate, bare chest, traces of drapery on far shoulder usually visible, right
  • Bust of Hadrian, laureate, cuirassed, right, viewed from front
  • Bust of Hadrian, laureate, draped and cuirassed, right, viewed from front
These three types have been derived from a single type in the original volume, 2C. Since few, if any, other collections have begun to catalog their collections in the new type numbers, if we published every type without linking Hadrian 4-6 as a supertype, we would end up losing all of the specimen data from Hadrian 2C. There is certainly a disadvantage to this approach, which can be illustrated in Hadrian 14-16:

While II.3 Hadrian 14 maps 1:1 with II Hadrian 4B, II.3 Hadrian 15 and 16 both map to one type in the first edition (4C). Therefore, the same example specimens appear under the Hadrian 15 and 16 types, not having been disambiguated by bust type in the source cataloging from partner collections. We hope these sorts of issues will be cleaned up over time.

On the other hand, the supertype strategy does open the door to archaeological materials to be attributed to the supertype, when the bust is too worn for certain identification.

The Concordance List

Lauren worked to put together a concordance list between the old and new type numbers, which we have published as a Google Sheet here. The relationship is often 1:1, but there are 1:n relationships in either direction. Under the hood in Numishare, 1:1 relationships result in an HTTP 303 See Other redirect to the new type URI. If an old URI corresponds to more than 1 new URI, the user is presented with a choice of possibilities (example, http://numismatics.org/ocre/id/ric.2.hdn.4C). The underlying RDF data include dcterms:replaces/dcterms:isReplacedBy and skos:exactMatch properties, according to precedents we have established in other projects, like Ptolemaic Coins Online.

There are some 400 type numbers from the first edition that are not in the second, including cistophori, which have moved to Roman Provincial Coinage. We plan to create automated redirects to RPC Online for this block of about 100 types in the near future.

Tuesday, May 19, 2020

British Museum URIs updated, linked to Coin Hoards

More than 62,000 British Museum coins that have been aggregated into the Nomisma.org numismatic Linked Open Data cloud have had their URIs updated to the newly-launched Collections Online system. The lack of long-term maintenance of their own URI scheme has been a well-known problem for years, and hopefully the new Collections Online receives the administrative backing to promote a greater level of stability than the original experiment with SPARQL.

As part of this overhaul, my script read a JSON API for each coin to perform a lookup of new image URLs. The images provided in the new system are higher resolution than before, enabling us to store both thumbnail and maximum resolution image links. In some cases, we have been able to prefer obverse and reverse images over jpegs where these sides had been combined into one file.

In addition, I performed a lookup for Greek coins with "hoard" as a keyword. I downloaded the CSV for these search results (1,600 coins), and was able to link about 1,400 of them to URIs in coinhoards.org. Surprisingly there was zero overlap between Hellenistic coins from the BM that were already in PELLA, SCO, and PCO and coins with hoard references. I imagine this is a gap in cataloging. I also used OpenRefine to reconcile mints, denominations, and materials to Nomisma URIs so that these values can be used for more sophisticated query.

A British Museum coin linked to IGCH 1648.
These 1,400 coins have been linked positively to 38 IGCH hoards, including seemingly complete coverage of IGCH 2194, a hoard consisting exclusively of Carthaginian bronzes. The British Museum's cataloging suggests these were all minted in Carthage, but IGCH suggests an uncertain Siculo-Punic mint.

About half of all of the coins with an IGCH reference come from IGCH 1355, a substantial hoard of Rhodian silver coinage. Sadly, few if any have been photographed so far.

Thursday, May 14, 2020

More than 1000 monogram URIs added to more than 2,000 types of Alexander the Great

Back in December, more than 1,200 monograms from Price's 1991 monograph, Coinage in the Name of Alexander the Great and Philip Arrhidaeus, were published into PELLA, each accessible at a URI with at least one SVG graphic (drawn by Mark Pyzyk) representing an idealized representation of that monogram.

Recently, we processed a concordance between these monogram IDs and their associated Price type numbers (also prepared by Mark) and regenerated the entire Price data in PELLA. The result is nothing short of major advancement in the way researchers can query and visualize these monograms over time and space.

Fig. 1: monogram facets
Let's first begin with the browse page, where the symbol facets (expand the list below the typological categories) have been updated for these monograms. The multiselect widget supports rendering HTML, which means we can display the SVG graphic in the symbol list (Fig 1). If we select one or more monograms to filter our search results, the graphic will also display in the list of filters to be removed (Fig 2).

Fig. 2: search results

Connecting all of the dots in the numismatic LOD graph

Monogram 453 is one of the more interesting test cases.

Of course the monogram will appear on a type page which contains that monogram, e.g., Price 210, and it will also appear in MANTIS as well, since MANTIS (and other Numishare-based projects) will pull typological data from a coin type record. The ANS coin, 1944.100.29329, has a type of Price 210, but was also found in the the Demanhur Hoard (IGCH 1664), which now enables us to establish a direct link from specimen -> hoard (with findspot) -> type (with mint) -> monogram. Since this monogram appears on many types which are linked to many specimens from various hoards, we can therefore generate a map showing the geographic distribution of both production and circulation of this monogram. We can also get a full list of types on which this monogram appears. We can see that it was overwhelmingly produced from 336 - 300 B.C., but still produced in Miletus as late as 165 B.C.

Fig. 3: Monogram 453

The next logical step for this is to expand the map to include a histogram reflecting both periods of production and the deposit dates of the related coin hoards. The hoard GeoJSON is already GeoJSON-T compliant.

Furthermore, since Price types have been annotated, you can see Edward T. Newell's own sketch for this monogram in one of his own research notebooks in our digital archive (powered by TEI - IIIF interoperability).

Page 19 of one of Newell's hoard notebooks.


Because we have captured constituent letters of these monograms (using CIDOC-CRM, as detailed in the December blog post), it is possible to take these visualizations one step further by showing the distribution of a particular letter or combination of letters over time and space. Although we have not adapted the Numishare user interface to query and visualize by constituent letters yet, it is nevertheless possible to conduct these queries directly in Nomisma.org's SPARQL endpoint.

Because there are a number of similarities across monograms (see http://numismatics.org/pella/symbols?symbol=%CE%94&symbol=%CE%97 for monograms with Η and Δ), perhaps we would like to query for all mints that contain monograms that include both of these letters:



PREFIX crm: <http://www.cidoc-crm.org/cidoc-crm/>
PREFIX geo: <http://www.w3.org/2003/01/geo/wgs84_pos#>
PREFIX nmo: <http://nomisma.org/ontology#>
PREFIX org: <http://www.w3.org/ns/org#>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX skos: <http://www.w3.org/2004/02/skos/core#>

SELECT DISTINCT ?mint ?label ?lat ?long WHERE {
  ?monogram crm:P106_is_composed_of "Δ", "Η" .
  ?side nmo:hasControlmark ?monogram .
  ?type nmo:hasObverse|nmo:hasReverse ?side
  {?type nmo:hasMint ?mint}
  UNION {?type nmo:hasMint/rdf:value ?mint}
  ?mint a nmo:Mint ;
        geo:location ?loc ;
        skos:prefLabel ?label FILTER (langMatches(lang(?label), "en")) .
  ?loc geo:lat ?lat ;
       geo:long ?long
} 



Distinct mints with delta-eta (results)

Or perhaps we want to see not just the distinct mints, but the full list of types (mapped) and ordered chronologically (query):

https://tinyurl.com/y7puekgg

Broad distribution of delta-eta monograms, grouped geographically by number of types

What we see here is that eta and delta monograms first appear in Miletus about the time of Alexander's death before circulating around neighboring cities in Asia Minor, then substantial production in Ecbatana from 295-280 B.C., and then two notable periods in Odessus in 200 B.C. and again in 70.

Next Steps 

The obvious next step is to upgrade the interface of the symbol page to generate a map of mints and findspots for a given letter combination, as well as provide links to download related coin types and physical specimens. This is fairly straightfoward and can be implemented within the next several days.

Currently, Lauren Tomanelli (having finished her work on the new Hadrian volume of RIC) is working on preparing the Ptolemaic monograms for publication, and Oliver Hoover is doing the same for the Seleucids. Seleucid Coins Online and Ptolemaic Coins Online will be reprocessed with these new URIs, and so this functionality will become available in both of those projects, as well as in the Hellenistic Royal Coinages umbrella site. There will be some duplication of monogram forms across these corpora. In the longer term, the Greek numismatists working within the Nomisma community will disambiguate these monograms and issue a new URI pattern directly in Nomisma for each distinct monogram. Old, duplicate URIs from HRC will point to the new scheme.

Thursday, April 30, 2020

Updates to Coin Hoards of the Roman Republic

With the impending launch of the new database of Greek Coin Hoards (derived from the 1973 publication, Inventory of Greek Coin Hoards), which will implement an updated findspot model that results in an RDF model more in line with ARIADNE's CIDOC-CRM recommendations, I have made some updates to Coin Hoards of the Roman Republic. Both hoard projects now export compatible Linked Open Data.

Instead of linking directly to a Geonames URL for the findspot (which can result in a collision of triples when aggregating content across collections that use the same gazetteer), the findspot is essentially reconceived as having been found within the boundaries of the gazetteer place, but is not that place itself.

Similar to a proposal I submitted to integrate the ARIADNE findspot data model into Linked Art, the new model extends nmo:hasFindspot from a direct gazetteer link to a node represented an nmo:Find (event), roughly equivalent to CRM sci:S19_Encounter_Event.


<http://numismatics.org/chrr/id/BAL>
  a nmo:Hoard, skos:Concept ;
  skos:prefLabel "Balanesti (Romania; BAL)"@en ;
  nmo:hasClosingDate "-0078"^^xsd:gYear ;
  nmo:hasFindspot [
    a nmo:Find ;
    crm:P7_took_place_at [
      a crm:E53_Place ;
      rdfs:label "Balanesti, Romania"@en ;
      crm:P89_falls_within <https://sws.geonames.org/685694/>
    ]
  ] ;
  dc:tableOfContents <http://numismatics.org/chrr/id/BAL#contents> ;
  void:inDataset <http://numismatics.org/chrr/> .

<https://sws.geonames.org/685694/>
  a crm:E53_Place ;
  rdfs:label "Bălăneşti (Romania)" ;
  crm:P2_has_type <http://vocab.getty.edu/aat/300008347> ;
  geo:location <https://sws.geonames.org/685694/#this> ;
  crm:P168_place_is_defined_by <https://sws.geonames.org/685694/#this> .

<https://sws.geonames.org/685694/#this>
  a geo:SpatialThing, crmgeo:SP5_Geometric_Place_Expression ;
  crmgeo:Q9_is_expressed_in_terms_of <http://www.wikidata.org/entity/Q215848> ;
  geo:lat 45.06667 ;
  geo:long 23.4 ;
  crmgeo:asWKT "POINT (23.4 45.06667)"^^http://www.opengis.net/ont/geosparql#wktLiteral .


The geographic coordinates are still linked/encoded with the W3C WGS ontology (geo:) to remain compatible with our practices elsewhere in the Nomisma data model, but also implemented crmgeo for encoding points and polygons as WKT, and designate the spatial node with both the geo:SpatialThing and crmgeo:SP5_Geometric_Place_Expression RDF classes.

In the process of developing a stylesheet to make some minor updates to the underlying NUDS Hoard XML model, I discovered numerous missing or inaccurate Geonames place references. Many of the missing places were cities in the former Yugoslavia, which did not match anything in the automated Geonames lookup we devised for this project back in late 2012/early 2013. Many of these places have mapped to modern cities in Slovenia, Croatia, other countries.


Improved coverage in the former Yugoslavia

Other corrected places may have been Romanian or Italian administrative divisions instead of the lower-level populated place. The Geonames place codes have been resolved to Getty Art & Architecture Thesaurus terms, which have been reindexed into CHRR as a facet on the browse page.

Another area where a few gaps were filled came with Nomisma IDs for extraneous authorities that have only recently been created for IGCH, e.g., Juba I. With these authorities having been linked to Nomisma, the reindexing process has pulled the related dynasties and corporate entities related to these people and exposed them as new facets in the browse page.


Furthermore, since the coins of Juba I appear in more than a dozen Roman Republican coin hoards, these hoards now populate the geographic distribution in the map on his Nomisma page.

Distribution of Republican coin hoards including the coins of Juba I

Thursday, April 23, 2020

Bronze types from Ptolemy I - IV published to PCO

More than 500 bronze coin types from Catharine Lorber's Coins of the Ptolemaic Empire Vol. I, Part II (Ptolemy I - IV) have been published online to Ptolemaic Coins Online. You can access them by selecting Bronze from the material facet in the browse page: http://numismatics.org/pco/results?q=material_facet%3A%22Bronze%22.

Many thanks to Gunnar Dumke at Martin-Luther-Universität Halle-Wittenberg for working on this spreadsheet. It was essentially publication ready, except for a few new Nomisma IDs for authorities and denominations that needed to be created.

The next task is to export a new batch of coins from the American Numismatic Society collection that will map to these new URIs through the underlying Svoronos concordances.

The coins from the British Museums (for example, http://numismatics.org/pco/id/cpe.1_2.B508), were already ingested with Svoronos URIs, and automatically show up in CPE types via skos:exactMatch links in the underlying Linked Open Data. Unfortunately, the BM coins aren't photographed.

Update: April 24, 2020


The ANS coins with Svoronos references have been exported from our curatorial database into MANTIS. Nearly six hundred bronzes have been linked to the new PCO URIs and integrated into Nomisma.org's SPARQL endpoint for query and analysis. There are now about 3,200 Ptolemaic coins linked to PCO, more than half of which have come from the ANS collection. Both the British Museum and Bibliothèque nationale de France have contributed more than 600 coins, and another nine institutions of varying sizes have contributed the remainder.

Tuesday, March 24, 2020

First batch of Philip II coins added to PELLA

The first few collections of Philip II coins have been linked to new Le Rider URIs and have been made accessible in PELLA through Nomisma.org's SPARQL endpoint. The American Numismatic Society linked 656 coins to these new URIs. Over the weekend, Karsten Dahmen at the Berlin Münzkabinett cataloged the first 17 coins of their collection. Additionally, I used Matt Lincoln's old data dump of years-old British Museum RDF data running locally in an endpoint to query for Le Rider references among their coins. Using OpenRefine to perform some additional cleanup, almost 60 coins of Philip II from the British Museum are now available in PELLA. Furthermore, just about a half hour ago, Julien Olivier at the Bibliothèque nationale de France sent a spreadsheet of 202 coins of Philip II with their corresponding Le Rider URIs. At this phase, there are now over 900 physical specimens linked into these typologies in PELLA. Not bad since we only just published them less than a week ago!

PELLA Philip II 137 is one of the best-represented types.


I expect a lot more contributors to come along as the cataloging process begins to proliferate through partners such as KENOM and NUMiD.

As it stands now, there are 382 total parent types in PELLA. The coins from the aforementioned collections are cataloged with a mixture of Le Rider (subtype [skos:broader] or skos:exactMatch [for plate-figure numbers]) URIs and PELLA parent type URIs. With the following SPARQL query, I can get a count of the number of photographed specimens per type:

PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX dcterms: <http://purl.org/dc/terms/>
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
PREFIX nm: <http://nomisma.org/id/>
PREFIX nmo: <http://nomisma.org/ontology#>
PREFIX skos: <http://www.w3.org/2004/02/skos/core#>

SELECT ?type (count(?coin) as ?count) WHERE {  
  ?type dcterms:source|skos:exactMatch/dcterms:source nm:pella_type_series .
  ?coin nmo:hasTypeSeriesItem|nmo:hasTypeSeriesItem/skos:broader ?type .
  {?coin nmo:hasObverse/foaf:depiction ?img}
  UNION {?coin foaf:depiction ?img}
} GROUP BY ?type


Hoards of Philip II coins
There are 258 types of Philip II with at least one photographed specimen, which is about two-thirds of the entire range of coinage. Not too bad for just several collections working together to catalog their coins in a few days.

Now that we have linked the Philip II Nomisma ID to typologies and specimens, some of these specimens also include hoard references, therefore populating the Philip II URI with additional research context for geographic and statistical visualization.

Average weights of tetradrachms from Philip to Alexander

As you can see from the chart above, the weight of Macedonian tetradrachms remains consistent from Philip II to Alexander until 336 B.C (https://bit.ly/2wCuH8G).

Thursday, March 19, 2020

The gold and silver coinage of Philip II published to PELLA

After considerable effort by ANS curator Peter van Alfen, the gold and silver coin types of Philip II of Macedon have been published to PELLA. This typology, based on Georges Le Rider's 1977 Le monnayage d’argent et d’or de Philippe II frappé en Macédoine de 359 à 294, has been numbered 1-382. Le Rider's corpus is actually a die study, and the numbering system is based on die combinations rather than types. As such, there are about 2,200 or so die combinations that correspond to the 382 types. These types were given a new numbering scheme, pella.philip_ii.1 to 382, but all of the Le Rider numbers are also URIs in order to establish a concordance between Le Rider and the new scheme so that collections that cataloged their coins with Le Rider numbers can submit their RDF with those URIs or map the Le Rider to the PELLA type number.

Le Rider numbers as subtypes or deprecated types

The correspondence between PELLA and Le Rider numbers is either 1:n or 1:1. When a typology has multiple possible die combinations, the Le Rider number is considered to be a subtype of the PELLA super type. For example, there are three die combinations for PELLA Philip II no. 1, Le Rider 1.1 to 1.3. If a museum has cataloged one of their coins to Le Rider 1.1, that coin will show up on the subtype page for that combination as well as the page for PELLA Philip II 1, which gathers all of the physical specimens linked directly to that URI or any possible subtype URI (via Nomisma.org's SPARQL endpoint).

Philip II 125 with the first specimen from a Nomisma partner.


The other category in which a PELLA and Le Rider number might correlate is 1:1. In these cases, the Le Rider URI still exists, but is not a subtype (linked in the RDF as skos:broader). Instead, the Le Rider Linked Open Data is dcterms:isReplacedBy the PELLA URI, which forces an automatic semantic HTTP 303 redirect in the browser (e.g., Le Rider 5.120). The underlying RDF for the Le Rider URI is still accessible through content negotiation or appending .ttl, .jsonld, or .rdf onto the URI. These two URIs are still linked together by skos:exactMatch, which facilitates the display of coins linked to Le Rider URIs on the PELLA page.

Uploading spreadsheets in Numishare

The publication of this typology represents a breakthrough in another way. Last summer, I spent several weeks developing a spreadsheet import mechanism in the Numishare back-end. I detailed it here (along with recommendations for structuring numismatic data in Google Sheets). After some further tweaking this week, the Philip II typology is the first spreadsheet data imported into Numishare in production. Out of all of the typology projects we have published online in the last 8 years (since the OCRE prototype developed in 2012), this is the first one that did not require me to write an intermediate PHP script. I cannot overemphasize how important this is. Curators can now formulate their own data, according to the specifications above, and publish new projects without technical intervention. After the conclusion of the Hellenistic Royal Coinages project in May, I will turn my attention to refactoring older spreadsheets from OCRE into this new format, and major updates in OCRE can be made directly by curators. I have essentially coded myself out of a repetitive task, saving myself a lot of time and the ANS a lot of money in the long term.

What's next for PELLA?

Now that the URIs for Philip II are activated, I imagine that our colleagues in Berlin and Paris will begin cataloging with them. Peter has updated our curatorial database with these new IDs, but the data have not been pushed from our [terrible] FileMaker database to Mantis, but you should expect to see the ANS's coins of Philip II online in the coming days. In the mean time, a single tetradrachm from the Fralin Museum at the University of Virginia is the first contributor to the new corpus, for Philip II 125.

Tuesday, March 10, 2020

About 800 "Greek" concepts published to Nomisma

After two weeks of solid research and data entry labor by Andy Meadows and I (and after review by the Greek committee), about 800 new or updated concepts corresponding to the Greek world have been published to Nomisma.org in three spreadsheets. These entities include people (rulers, usually) and their associated dynasties and corporate entities. Aside from people and organizations we typically consider "Greek", these lists include entities from other domains that have always been historically part of the study of broader Greek coinage, including Parthian, Indo-Scythian, Numidian, Arabian, etc. These entities aren't a comprehensive listing of every possible ruler that issued coinage from a particular realm, but form a large portion of these rulers, reflecting the combination of an older spreadsheet of rulers with the entities necessary for the publication of a new Inventory of Greek Coin Hoards database (as part of the NEH-funded Hellenistic Royal Coinages project). Corporate entities can be separated into their own spreadsheets for further revision by subject specialists in order to fill in gaps.

What's useful is that while we are able to use the W3C Org ontology to link people to their roles in larger corporate entities (and the start and end dates of their reign(s)), we are also able to apply the same org:Membership model to link one foaf:Organization to a larger one. That is to say, the Kingdom of Cimmerian Bosporus was independent from 438-107 B.C., but from 107 to 63 was part of the Kingdom of Pontus, and from 63 B.C. to 370, operated as a client-kingdom of Rome.

This enables us to execute queries for all of the lesser kingdoms that served as client-states of Rome:

SELECT * WHERE {
  ?org a foaf:Organization ;
         org:hasMembership/org:organization nm:roman_empire ;
         skos:prefLabel ?label FILTER (langMatches(lang(?label), "en"))
}

This can be taken a step further to list the client-kings of Rome by means of the link between the ruler and their kingdom and dates of their reign and filtering it against the date range in which that kingdom was a client-kingdom of Rome.

SELECT ?person ?p_label ?p_start ?p_end ?org ?label WHERE {
?org a foaf:Organization ;
         org:hasMembership ?membership ;
         skos:prefLabel ?label FILTER (langMatches(lang(?label), "en")).
  ?membership org:organization nm:roman_empire ;
              nmo:hasStartDate ?client_start;
              nmo:hasEndDate ?client_end .
  ?person org:hasMembership ?pMembership ;
          skos:prefLabel ?p_label FILTER (langMatches(lang(?p_label), "en")).
  ?pMembership org:organization ?org ;
               nmo:hasStartDate ?p_start ;
               nmo:hasEndDate ?p_end .
  FILTER (?p_end > ?client_start && ?p_end < ?client_end)
} ORDER BY ?org ?p_start

The query above results in the following table of rulers sorted chronologically. The first client-king of Bosporus is Pharnaces II, the son of Mithradates VI, who took over in 63 B.C.

Now that the publication of these entities is complete, I will turn my attention back to reconciling authorities in IGCH data in OpenRefine. The new coin hoard database should be ready by the end of March, and it will facilitate new modes of query that include querying by dynasty and corporate entity by means of the person-org/dynasty relationship inherent in Nomisma's LOD data model. Greek numismatists will finally have a decent open access tool for coin hoard research, coupled with the publication and interlinking of our archival records in Archer.

Wednesday, January 8, 2020

A closer look at the Nomisma monogram data model

After the launch of more than 1,200 monograms that appear on the coinage of Alexander the Great as part of the PELLA project, I have made some updates to the data maintenance framework that underlies Nomisma.org. These changes enable monogram datasets to be added/removed via revised SPARQL/Update queries that incorporate CIDOC CRM properties to link to image files and the W3C PROV ontology for data provenance (similar to the model we already implement for Nomisma concept URIs). Note that the PROV ontology is not used for data provenance for coin type corpora or hoard databases, although this is something we should consider implementing at some point.

Introduction to the Monogram/Symbol data model

Monograms published to the web follow a similar pattern to other SKOS concepts in our ecosystem. The RDF class is nmo:Monogram from the Nomisma ontology. Our ontology will be updated soon to give nmo:Monogram a superclass of CIDOC CRM's E37_Mark. Any other symbol that appears on a coin (which can be letters used as control marks or mint marks and pictographic symbols, such as "torch" or "ram's head") are also E37_Marks. The definition of a Mark is as follows:

This class comprises symbols, signs, signatures or short texts applied to instances of E24 Physical Man-Made Thing by arbitrary techniques in order to indicate the creator, owner, dedications, purpose, etc.

All symbols are inherently concepts and have one required skos:prefLabel and one skos:definition in English. Like other concepts, there might be a Field of Numismatics (dcterms:isPartOf) or Bibliographic reference (dcterms:source) pointing to Nomisma URIs.

Since all symbols are E37_Marks (directly or indirectly), we are able to use some other CIDOC CRM properties. The crm:P106_is_composed_of property points to constituent letters or symbols. Typically, this is letter, but we have at least a few examples of RIC 10 monograms that are composed of letters and Christograms. When we publish a new edition of these monograms into OCRE, we are going to create the Christogram URIs in a new /symbol/ namespace in Nomisma.org. Using property paths, it will be possible to execute a SPARQL query for any monogram that includes a Greek rho, regardless of whether this letter appears directly in the monogram or is part of a monogram that is contained within a monogram.

<http://numismatics.org/pella/symbol/monogram.price.1000>
  a nmo:Monogram, skos:Concept ;
  skos:changeNote 
    <http://numismatics.org/pella/symbol/monogram.price.1000#provenance> ;
  void:inDataset <ttp://numismatics.org/pella/> ;
  crm:P106_is_composed_of "Κ", "Υ", "Ο" ;
  skos:prefLabel "Price Monogram 1000"@en ;
  skos:definition "Monogram 1000 from M.J. Price, Coinage in the Name of Alexander the 
    Great and Philip Arrhidaeus: A British Museum Catalogue. The monogram contains 
    Κ, Υ, and Ο as identified by Peter van Alfen."@en ;
  dc:source <http://nomisma.org/id/price1991> ;
  dc:isPartOf <http://nomisma.org/id/greek_numismatics> ;
  crm:P165i_is_incorporated_in 
    <http://numismatics.org/symbolimages/pella/monogram.price.1000.svg> .

We link to one or more digital image files representing an idealized view of the monogram or symbol with the property, crm:P165i_is_incorporated_in. At the recommendation of the CRM SIG, this digital image (an SVG file: see Github for the full repository of monograms SVGs) bears a crmdig:D1_Digital_Object class and some additional triples about the license (CC Public Domain Mark), the ORCID of the graphic artist who drew them (Mark Pyzyk), and the mime-type as dcterms:format.

<http://numismatics.org/symbolimages/pella/monogram.price.1000.svg>
  a crmdig:D1_Digital_Object> ;
  dc:format "image/svg+xml" ;
  dc:creator <https://orcid.org/0000-0001-7542-4252> ;
  dc:license <https://creativecommons.org/choose/mark/> .


Like Nomisma concepts, these monograms have some provenance metadata, linking them to Peter van Alfen's Nomisma editor URI as the contributor (of the constituent letters) and a link to a source Google Spreadsheet. These monograms were imported into PELLA through a new symbol spreadsheet import functionality implemented in the Numishare platform itself. It operates much like the spreadsheet import in Nomisma, parsing the spreadsheet and transforming rows into RDF files that get stored in Numishare's eXist-db XML database.

While there is a basic interface built into PELLA (and other monogram corpora when they get published in Numishare) to query by constituent letter based on XQuery of the XML database, ultimately, I plan to implement a unified interface for this sort of query directly in Nomisma.org which will be based, instead, on SPARQL (see this basic example query). This will open the door to querying across many type corpora (Seleucid and Ptolemaic coinage combined), as well as exploit the relationships between letters, monogram URIs, and coin types that have been linked to those monogram URIs, paving the way to extract lists of mints, authorities, etc. connected to certain letters, and sort these by chronology or other categories. This is merely the tip of the iceberg in new forms of query of numismatic data that were never previously possible at this scale, made possible by Linked Open Data methodologies.