University of Heidelberg joins Nomisma

The Centre for Ancient Studies of Heidelberg University is the newest member of the Nomisma.org consortium. The Seminar für Alte Geschichte und Epigraphik of Heidelberg University together with the Institut Klassische Archäologie holds a collection of more than 4,000 Greek and Roman coins. The collection dates back to Georg Friedrich Kreutzer (1771-1858) and grew with later purchases and donations. From the beginning, the collection was conceived to be used for teaching purposes, highlighting the history of coinage from its origins in ancient Greece down to Late Antiquity. The collection is available online at http://pecunia.zaw.uni-heidelberg.de/ikmk/. The university presently contributes about two dozen items to OCRE and CRRO (see RIC Nero 2, for example),  but this contribution will grow as the collection continues to be digitally cataloged.

Distribution Analysis of Portraits and Deities

Building on recent advancements in distribution visualizations I rolled into production on Nomisma.org last month, I have extended the complexity of these visualizations to include portraits and deities both as distribution categories and parameters for generating subsets of results from the Nomisma SPARQL endpoint. Deities, in particular, required some extra work. While we have incorporated URIs from the British Museum thesaurus for deities into our data throughout ANS projects, there had been no accompanying triples for these URIs to provide human-readable labels. I wrote a simple script to extract labels from the British Museum SPARQL endpoint in order to generate a fairly simple SKOS-based taxonomy for the entities, which I then uploaded into Nomisma's endpoint. You yourself can download this small RDF dataset from http://nomisma.org/datasets.

Distribution of mints for Augustan coin types of Victory vs. Mars

This required rewriting the underlying XSLT templates in the XPL for generating the XML model (which would be serialized into the JSON view required by d3plus, a chart extension for d3js). The previous XSLT stylesheet stored a generic SPARQL query as text, which had bits and pieces replaced with variables passed in via HTTP request parameters. This worked well enough when querying predicates stored directly within the coin type data object. However, portraits and deities are expressed at a deeper level--within the triples describing the obverse or reverse of the coin. Thus, a query for coin types depicting Agrippina the Younger is as follows:

?s a nmo:TypeSeriesItem ;
  nmo:hasObverse ?obv ;
  nmo:hasReverse ?rev .
{?obv nmo:hasPortrait nm:agrippina_ii}
UNION {?rev nmo:hasPortrait nm:agrippina_ii}

As a result, the simple textual search-and-replace technique for constructing the SPARQL query was reconceived as a data object (represented as XML within an XSLT variable) generated by HTTP request parameters. Each triple XML element contains a subject, predicate, and object attribute. Union and optional queries are contained within relevant XML tags.

<triple s="?coinType" p="nmo:hasObverse" o="?obv"/>
<triple s="?coinType" p="nmo:hasReverse" o="?rev"/>
<union>
    <triple s="?obv" p="nmo:hasPortrait" o="{$object}"/>
    <triple s="?rev" p="nmo:hasPortrait" o="{$object}"/>
 </union>

Where the $object is the object in the "compare" or "filter" request parameter (in this case, nm:agrippina_ii). This XML expression of a SPARQL query is then transformed via XSLT templates into the plain text which is then used to GET the response from the endpoint. I have posted this XSLT stylesheet to gist.

Enhancing geographic distribution

I added one little, but very useful tweak. As previously discussed, the data for any visualization can be downloaded as a CSV file. I enhanced this CSV file by including the entity URIs, but, more importantly, when the distribution category is set to "Mint", the underlying SPARQL query will extract the latitude and longitude if available. As a result, you can drop the CSV directly into Google Fusion Tables to generate a map or import it into GIS software (like QGIS), and using the count or percentage column, adjust the size or coloration for a more accurate, graduated visualization (like below).

Distribution of Augustan issues depicting Victory

800 Alexanders from the Ashmolean added to PELLA

The Heberden Coin Room of the Ashmolean Museum, University of Oxford is the newest member of the Nomisma consortium of data contributors. Thanks to the cataloguing of Simon Glenn, we were able to create a concordance between 800 coins of Alexander the Great and URIs published in PELLA. I received a CSV dump of these coins yesterday, and wrote a simple PHP script to convert Price numbers into PELLA URIs and generate Nomisma-compliant RDF, which was just published into Nomisma's SPARQL endpoint.

A number of these coins from the Ashmolean were linked to IGCH URIs on Coinhoards.org, and so findspots are available in both PELLA directly and also in the maps of associated Nomisma.org numismatic concept pages. For example, Price 4 now shows a point for IGCH 1670, a hoard found in Egypt. Likewise, the Nomisma ID for tetradrachm (the denomination of Price 4) also shows this findspot in the geographic distribution of mints and finds for that denomination.

Many thanks to those involved at the Ashmolean Museum for their contribution in furthering the study of Greek numismatics.

RIC 9 published to OCRE

RIC volume 9 has been published to Online Coinage of the Roman Empire. This represents about 1,700 types and 3,200 subtypes. In total, there are now more than 43,000 Roman Imperial coin types in OCRE, spread over half a millennium from Augustus to Zeno. This was a huge undertaking with many collaborators from the ANS and DAI, as well as contributors of data from more than a dozen American and European cultural heritage institutions. Without generous support from the National Endowment for the Humanities, we may never have completed this project, which will officially come to a close in December. Since publishing the types to OCRE yesterday, I have begun the process of harvesting relevant coins from partner institutions. The British Museum alone has contributed an additional 11,600 RIC 9 coins to OCRE, and the total number of physical specimens linked into the project stands around 93,000. We hope to surpass 100,000 when the ANS and Fitzwilliam Museum coins are added soon.

While some more work remains in tying up loose ends regarding meeting every specification of the NEH grant (with respect to correcting reference numbers in our curatorial database and completing photographic coverage of our Imperial coinage), we are nearing the final phase of the project, which will draw to a close by the end of the year. Nevertheless, the project will continue to evolve in a variety of ways. We anticipate aggregating content from more partners, especially from the archaeological community. There are more than 200,000 Roman Imperial coins in the Portable Antiquities Scheme, but so far barely over 300 have been linked to OCRE URIs. I am continuing to build more sophisticated analysis and visualization interfaces. These advancements have been implemented directly in Nomisma.org, but I anticipate porting these code updates into OCRE and various other Numishare-based coin type projects. We also plan to unveil two new features by the end of this year: an intuitive coin type identification interface that non-specialists (collectors or archaeologists working in the field) might use to identity coins, and a faceted search function for architecture depicted on Roman coinage (which extends into Republican coins in CRRO).

While the NEH funding was instrumental in the development of OCRE specifically, the open source code and the workflows we developed for this project have had an impact on our ability to publish similar online type corpora. In 2015, we saw the release of Coinage of the Roman Republic Online and PELLA. Since the multilingual and visualization functionality are inherent to Numishare, our other projects benefit from the funding the NEH invested directly into OCRE. One of these, obviously, is the Egyptian National Library collection of Islamic coinage, which is available in both English and Arabic.

3,500 Fitzwilliam Museum (Cambridge) coins harvested into Nomisma

Using a combination of the University of Cambridge Fitzwilliam Museum's API to query for Roman Republican and Alexander the Great coins and PHP-based screen-scraping of reference numbers and measurement data, I was able to harvest more than 3,500 coins from the Fitzwilliam the other day. The script, which I have published to Github, took a few hours to write and another hour or so to fully execute.

The script queries the API and iterates through each page of the JSON response. Since coin type reference numbers are not stored or indexed into their ElasticSearch application, the script must request each HTML page from their public-facing database. With some XPath to parse the HTML and regex to look for RRC or Price numbers, matching numbers are checked against CRRO and PELLA to confirm the validity of the reference.

The metadata for each record are stored in an array, which is serialized into Nomisma-compliant RDF and a CSV concordance list when the process completes.

I hope to tweak the script and re-apply to Cambridge's Roman imperial coins. This will be a tremendous enhancement to OCRE, as we look to crossing over the 100,000 coin threshold in that project alone.

Distribution Visualization Tools in Nomisma.org

I have spent the last month working on and off on a new set of research tools in Nomisma.org's interface. As users of individual ANS type corpus projects (like OCRE) will know, we have exposed simple weight and diameter analyses and the distribution of typological categories (like denomination, mint, authority, etc.) as graphs through a visualization interface. These interfaces query only those coin types or physical specimens connected with the type corpus as a whole. Plainly, this means that the interfaces in OCRE only query coin types from RIC or display the average weights of coins that have explicitly been connected to URIs published by OCRE. Partners with find or excavation databases that contain uncertain coins are excluded from these queries, even if the portrait or mint can be positively identified, but the wear of the legend is too great to allow for a certain RIC attribution.

I have begun to implement distribution visualization interfaces directly in Nomisma that query its SPARQL endpoint. At present, the distribution analyses are based on coin types. For example, you can generate a chart that shows the distribution of denominations issued by Augustus. You can place further filters on this query, for example, to show the distribution of denominations issued by Augustus at the mint of Rome. The interface allows you to gather multiple datasets for comparison, e.g., to include the distribution of denominations for Nero and Hadrian. These queries factor in all coin types, regardless of the scope of the type series, enabling you to query across all coins of the Roman Republic and Empire simultaneously.

Distribution of denominations of Augustus, Nero, and Hadrian from the mint of Rome

Some work remains in enhancing the complexity and scope of these queries. It is important to introduce start and end date filters so that it would be easier to evaluate changes in distribution over time. Furthermore, the categories for visualization (authority, issuer, mint, region, denomination, material, object type) need to be expanded to include portraits and depicted deities. This adds a layer of complexity in the query--these objects are referenced in the obverse and reverse of the coin type, not directly in the coin type data object itself. Presently, deities are an underutilized query parameter across all our projects. We use British Museum URIs, but have not integrated SKOS PrefLabels or any other properties about these URIs into the Nomisma SPARQL endpoint that would allow us to build a human-readable interface. Adding supplementary, non-numismatic datasets is on the agenda for Nomisma development.

The distribution analysis interface is available on the pages for individual Nomisma IDs (if these IDs have associated coin types) and on a separate interface. The distribution interface renders the chart by passing URL parameters to itself, so the page URL can be copied and pasted, and the charts can be shared with others. The charts on the Nomisma ID page are generated directly with ajax calls (so it is easier to view changes in the graph when modifying underlying queries), but you can click a button load the chart in the distribution page. There is an option to download the data as CSV in both interfaces.

Next: Metrical Analysis

Once I implement portraits, deities, and date filters, I will get to work on interfaces that will analyze weights and diameters. This interface will open the door to integrating physical coins that have been connected to typologies implicitly through OCRE, CRRO, and PELLA URIs or explicitly, enabling us to compare all coins of an emperor even when the specific coin type attribution cannot be ascertained.

These interfaces will not only show the average weights of typological categories, but changes in weight over time (e.g., to view the change in weight of the denarius over 400 years). I'll also implement standard deviation visualizations to cluster coins together of nearly identical weights, making it easier to spot outliers that might be fragmentary coins or even forgeries.

Remainder of RIC 5 Published to OCRE

Nearly 4,000 more types from the latter portion of RIC 5 have been published to Online Coins of the Roman Empire, predominately from the Gallic Empire and usurper sections. With RIC 5 completed, this brings to total number of Roman Imperial coin types to nearly 42,000. David Wigg-Wolf will finish checking the RIC 9 spreadsheet very soon. We expect to complete the project by the end of September (months ahead of schedule).

In many ways we have already exceeded the specifications of the NEH grant-funded project. The coins from the University of Virginia and Berlin have recently or are currently being processed to link to these new types. The ANS coins will become available in OCRE in the near future (as early as tomorrow). By the time RIC 9 is published and our partner collections have been reprocessed to add in physical representations of these coin types, OCRE will be very close to exceeding 100,000 coins from museum and archaeological databases. The number of partners and coins has increased in the last year, and we expect this level of growth to continue for the foreseeable future, especially with some of the major numismatic collections coming online (e.g., Vienna and the Bibliotheque nationale de France).

Since we are poised to finish the original parameters of the project three months early, we are going to work on adding value to our data by linking architecture displayed on coins to either broad architectural typologies (e.g., temple, fountain) or specific, known monuments (Temple of Mars Ultor). I think that this will open the door to more sophisticated query and analysis of Roman architecture and its relation with official imperial political messages to society (both in Rome and the provinces).

We are also going to work on putting together a user interface that will make it easier to identify coins, a feature that will be useful to casual collectors, museum curators, and archaeologists working in the field.

Nomisma.org crosses 100,000 coin threshold

Following the publication of RIC 6, 7, 8, and 10 to Online Coins of the Roman Empire, I extracted over 18,000 coins with references to these volumes from the British Museum SPARQL endpoint (with this query) and successfully matched and imported about 17,000 of these into Nomisma's SPARQL endpoint. There are now about 80,000 physical coins linked to the 38,000 Roman imperial coin types in OCRE. I also reprocessed the Berlin LIDO export and published 1,000+ coins from late Roman coinage into OCRE.

This recent import has brought the total number of physical specimens linked to online type corpora (including Coinage of the Roman Republic Online and PELLA) to 116,964, about 98,000 of which come from the British Museum and American Numismatic Society alone. The number of coins has more than doubled in a year.

Technical Process

The XML response to the SPARQL query linked above was processed through a PHP script I wrote several days ago. The script iterates through each result in the XML document in order to parse the reference text with regular expressions in order to generate a type ID that conforms to the OCRE convention (e.g., ric.7.anch.109) and test to see whether the URI exists. The result of the concordance process is written as a CSV file, which is then processed by another PHP script into RDF conforming to the Nomisma.org ontology. An additional SPARQL query is executed on the British Museum endpoint for each row in the table in order to extract the weight, diameter, image, etc. The RDF is written to disk and then imported into the Nomisma SPARQL endpoint, where the data are immediately available in OCRE.

ANS coins from RIC 6-10 published to OCRE, and other updates

Following the release of volumes 6, 7, 8, and 10 to OCRE, we have republished our coins from these volumes to link them into the newly-published coin type URIs. This represents an addition of more than 17,000 physical specimens of late Roman coinage into OCRE, including photographs for more than 3,000 of these (and photographic gaps from previous volumes of RIC). There are now 36,000 Roman imperial coins from the ANS collection in OCRE, and 60,000 in total from all our partners. Including CRRO and PELLA, there are just under 100,000 physical coins aggregated by Nomisma.org's SPARQL endpoint.

In addition to these coins, the Portable Antiquities Scheme provided access to several hundred imperial coins linked to OCRE URIs. The PAS had previously linked its entire collection of Republican coins (nearly 1,000) into CRRO, but the inclusion of imperial material in OCRE is a watershed moment for the study of Roman numismatics. These are the first few hundred of potentially hundreds of thousands of coins published in their database, each with attested findspots. This will have a dramatic effect on geographic analysis of ancient monetary circulation and trade.

The Harvard Art Museums API was also reprocessed. Harvard's coverage of late Roman coinage is quite good, and their contribution to OCRE has more than doubled to 1,300 coins.

Update (July 25): We have also added 174 coins published by OpenContext.org from the Domuztepe excavations into the Nomisma triplestore to make them available in OCRE. These are late Roman coins, predominately from RIC 7 and 8.

RIC 6, 7, 8, and 10 published to OCRE

After filling in gaps in Nomisma IDs necessary for the publication of RIC 10 (including the extension of Numishare to support the creation and publication of monogram URIs with images), we have pushed RIC 6, 7, 8, and 10 into Online Coins of the Roman Empire (OCRE). The symbol publication extension of OCRE can be seen at http://numismatics.org/ocre/symbols. Currently, each image is a PNG file, but will be replaced with SVG soon. We have developed a workflow to covert True Type Fonts representing Roman imperial numismatic symbols provided by Slovenian partners to SVG with a combination of the open source Linux tools, FontForge and Inkscape.

These four volumes represent a huge number of types, increases OCRE's types in excess of 13,000 up to a total that now exceeds 38,000. David Wigg-Wolf is working on the RIC 9 spreadsheet, and we hope to publish both that and the remainder of RIC 5 by the end of the year.

The next task for this OCRE update is to process several thousand images through our workflow and publish the coins in the ANS curatorial database that link to OCRE IDs into Mantis so that they will become available in OCRE via the Nomisma.org SPARQL endpoint.

Archaeological Museum of Münster University joins Nomisma

Thanks to the outreach conducted by the Berlin Münzkabinett and the reuse of their curatorial database platform, the  Archaeological Museum of Münster University has been integrated into the Nomisma.org consortium. There are a little over 40 coins that link to URIs for types published by CRRO, OCRE, and PELLA available so far. Those of you who use the Berlin database will recognize the similarity in the interface. Additionally, like the Berlin collection, the Münster database uses the same export mechanisms. I have updated my PHP scripts for processing Berlin's LIDO exports to make them more generalizable for the entire database framework so that I don't have to maintain multiple scripts for processing minutely different LIDO exports into Nomisma-compliant RDF. The script is available at https://github.com/AmericanNumismaticSociety/migration_scripts/blob/master/mk_scripts/process-exports.php

You can see an example of one of their coins at RRC 473/1, along with coins from the ANS, Berlin, Portable Antiquities Scheme, and the British Museum.

OCRE now available in Polish

With thanks to Adam Degler, translations for NUDS element names and interface components have been incorporated in Numishare. I re-indexed Online Coins of the Roman Empire into Solr, which has made the search and browse interfaces available in Polish (for facets; type descriptions are still only available in English). The facets are derived from SKOS preferred labels from Nomisma.org. The Polish coverage of Nomisma IDs relevant to Roman Imperial coins is nearly complete. I also re-indexed Coinage of the Roman Republic Online. The interface is available in Polish as well, but the coverage of Republican entities is not as complete as the Imperial period.

Nomisma.org Is Now a Functioning Pelagios Commons Hub

Given the interest of our partners (like Berlin and the Prehistory Museum of Valencia) in participating in the Pelagios Project, while perhaps lacking the funding to develop export scripts directly, I have extended the functionality of Nomisma to support exporting directly into the Pelagios Open Annotation RDF model. This was a fairly straightforward task which required two new XML pipelines in the Page Flow Controller in Orbeon: one for the VoID metadata RDF and one for the data dump (or dumps, since each dump is chunked into 5,000 coins).

The pipelines execute SPARQL queries that are piped through XSLT transformations into RDF. The VoID RDF aggregates subsets bound to the void:Datasets described in the Nomisma triplestore in order to provide descriptive metadata and license URLs for our partners (e.g., http://nomisma.org/pelagios-objects.void.rdf). The data dumps execute a SPARQL query that generates a list of nmo:NumismaticObjects linked to mints implicitly by coin types (nmo:hasTypeSeriesItem). Since ancient mints defined on Nomisma are linked to URIs in the Pleiades Gazetteer of Ancient Places, it is fairly simple to make ancient coins that have been ingested into the Nomisma triplestore available in Pelagios.

I also updated the Pelagios icon on the front page of Nomisma.

Lliria Hoard coins join OCRE

Nearly 6,000 Roman Imperial coins of the Lliria Hoard dating from Augustus to Commodus have been imported into Nomisma.org's endpoint and are available for geographic and quantitative analysis in OCRE. The coins of this hoard are now housed in two museums: the Prehistory Museum of Valencia and the Archaeological Museum of Lliria. All of the coins have been weighed and photographed, and since they each have attested findspots, they may be used to enhance the geographic visualization of the coin types from the hoard and the characteristics associated with these types (e.g., denominations or rulers). See http://nomisma.org/id/commodus for example. The Prehistory Museum of Valencia is our first Spanish partner.

Updating MANTIS and IGCH: Incorporating further context into our collection

For the first time, I am faced with a decision whether to post an update on the Numishare blog or XForms for Archives, my other blog for EADitor, xEAC, ETDPub, and our specific implementations of these frameworks within the American Numismatic Society.

I have been working significantly over the last few weeks in overhauling our infrastructure to interlink our projects more thoroughly. I have posted in the past about publishing our archival authorities and collections into a SPARQL endpoint in order to make these systems more interoperable. I extended this system so that our Digital Library publications would go into this endpoint as well, so that we can make our publications and archival materials available through our EAC-CPF collection (and vice versa). Last week, I re-wrote the TEI->RDF transformation in EADitor (for collections of facsimile images) to conform to the same Open Annotation model that I implemented for TEI EBooks published in the Digital Library.

This opened the door for specific mentions of coins, hoards, and other entities defined by URIs in Edward Newell's research notebooks to be made available in other systems, namely, in IGCH itself and through MANTIS.

For example, IGCH 1508 now contains two annotations for our library or archival materials--from Noe's recently published EBook Numismatic Notes and Monographs 1: Coin Hoards and one of Newell's research notebooks. It is possible to click on a link for any mention of these hoards on any page of the notebook or section of an EBook. Furthermore, IGCH has been extended further to display a list of coin types that appear in a hoard, with examples of coins (from PELLA). It is possible to download either all types or all coins from a hoard from the Nomisma.org SPARQL endpoint. See http://coinhoards.org/id/igch1399 for example.

The same basic code applies in MANTIS. Broadly speaking, Numishare has been updated so that it may read Open Annotations from an optional archival SPARQL endpoint (in this case, the endpoint is for Archer). It will display a link to a page or section that mentions a particular object in the ANS collection.

• A coin mentioned in a Newell notebook
• A medal mentioned in Miller's Medallic Arts of the American Numismatic Society 

I will be discussing the integration of these frameworks into a cohesive Library, Archive, and Museum linked data infrastructure at CAA in Oslo in several weeks.

Excavation coins from Priene available in OCRE

The Berlin Münzkabinett is setting up a new database for coin finds from German excavations of Priene:

This database includes the coins of the excavations since 1998 (Museum Balat) and the old excavations of the Berlin Museums (Münzkabinett, Staatliche Museen zu Berlin). By Bernhard Weisser and Johannes Eberhardt (Staatliche Museen zu Berlin) in cooperation with the German Archaeological Institute and the universities in Frankfurt (Wulf Raeck, Axel Filges), Bonn (Frank Rumscheid) and Bursa (Hakan Mert). IT: Jürgen Freundel, Editor: Karsten Dahmen.

So far there are two coins connected to currently published RIC types in OCRE (as a proof of concept), but more coins will be published eventually. The associated types are:

• http://numismatics.org/ocre/id/ric.5.cg.98
• http://numismatics.org/ocre/id/ric.5.gall(2).574

Since the two coins connected to these types have findspots, Priene will appear as a findspot on the map in OCRE. Additionally, with the more advanced mapping features recently introduced on Nomisma.org, the Priene findspot will appear on any map associated with any individual skos:Concepts connected to these coin types, e.g., Claudius Gothicus (http://nomisma.org/id/claudius_ii_gothicus), whose map shows a findspot for Priene and two hoards in Britain--Normanby and Oliver's Orchard Hoards--connected to coins from the University of Virginia.

Nomisma's new interface upgrades will be discussed in further detail in another blog post.

OCRE at the AIA/SCS in San Francisco

Andrew Meadows, one of the project managers for the Online Coins of the Roman Empire project, was in San Francisco today to present on a panel of NEH-funded projects in the archaeological realm, as part of the larger AIA/SCS conference. It generated a string of tweets (and replies) from Eric Kansa of OpenContext, which you can read at https://twitter.com/search?f=tweets&vertical=default&q=%23aiascs%20%40menetys&src=typd. Andy's presentation is more or less represented on Google Docs: https://docs.google.com/document/d/1QXSeOSNnV6-Zxe3dU_desqouTDcIEPIcT_XySZ8gMiA/edit. The presentation is effectively a summary of the state of the digital world of numismatics, including involvement in Pelagios and a crowdsourced coin identification project with MicroPasts to facilitate future integration of Portable Antiquities Scheme coins into OCRE.