Thursday, December 20, 2018

Ptolemaic Coins Online is officially released

After a lot of hard work by numerous people, Ptolemaic Coins Online is formally launched. This phase covers the gold and silver coinage from Ptolemy I - IV (volume I, part I) of Catharine Lorber's Coins of the Ptolemaic Empire. There are 990 total types (with some subtypes), with more than 1,700 specimens from 10 museums linked in.

CPE 158

PCO browse page

The press release is here:

Enhanced exploitation of concordances in type corpora

Today, I extended some Nomisma APIs (for weights and the widget that populates images in Numishare-based type corpora browse pages) as well as SPARQL queries in Numishare itself to make better use of concordances between corpora that we are encoding in our data and exposing as skos:exactMatch URIs in our RDF outputs.

I had recently extended these queries to support the display of subtypes in browse pages and under the main "Type Examples" heading on coin type record pages (e.g., on The logic behind this was to provide a better UI for researchers to view example images without having to drill down one or more levels to see individual specimens, particularly within Seleucid Coins Online, which routinely goes two levels down from the parent type.

With the launch of Ptolemaic Coins Online, which contains a fairly comprehensive concordance with Price URIs defined in PELLA for the earlier Alexander types, I felt we were leaving a lot of functionality on the table by not exploiting these links. They are exposed as skos:exactMatch properties in the RDF that is published to the SPARQL endpoint. The queries were extended in several areas of the codebase into the following:

{ ?object a nmo:NumismaticObject ;
 nmo:hasTypeSeriesItem <typeURI>}
UNION { <typeURI> skos:exactMatch ?match .
?object nmo:hasTypeSeriesItem ?match ;
  a nmo:NumismaticObject }
UNION { ?broader skos:broader+ <typeURI> .
?object nmo:hasTypeSeriesItem ?broader ;
  a nmo:NumismaticObject }

Since many of our partners have already cataloged and contributed coins with Price numbers, but have either not cataloged with the Svoronos 1904 or Coins of the Ptolemaic Empire numbers or have simply not provided data dumps for PCO, this has substantially extended the coverage of PCO. There are several hundred coins in the ANS collection with Price numbers, but no Svoronos. Instead of launching PCO with around 1,200 specimens from 4 or 5 museums, we are instead launching with 1,700 from 10.

The impact is especially noticeable among the earliest Ptolemaic coinage, where there is significant overlap with PELLA (the first several pages of the PCO browse page).

PCO browse page 1

Furthermore, we are able to exploit links to IGCH hoards that have been cataloged in the ANS collection for coins only linked to Price numbers. CPE 19 and 20 are both linked to more than 100 specimens (primarily in the ANS collection), and are each linked linked to several coin hoards.

CPE 19

Tuesday, December 18, 2018

University of Frankfurt joins Nomisma

The Coin Collections of the Goethe University, Frankfurt am Main is the newest contributor of the consortium, providing access to about 120 Roman Republican and Imperial coins. The Frankfurt collection is made available through the NUMiD project of German university museums, spearheaded by the Berlin Muenzkabinett database system. Including the Berlin collection itself, Frankfurt is the 17th NUMiD partner to be made available in this fashion.

Example of Augustus 15A.

Monday, November 26, 2018

University of Tübingen joins Nomisma

The University of Tübingen is the latest partner of the NUMID-driven consortium of German university museums to join and make their coins available in Online Coins of the Roman Empire and Coinage of the Roman Republic Online. There aren't many coins online so far (only 5 in Nomisma projects), but there are about 20,000 coins in the collection, most of which are ancient.

RRC 334/1

Tuesday, October 30, 2018

Seleucid Coins Online is [mostly] complete and published

After a few months of continuous work on normalizing data and fixing some type numbering issues, Seleucid Coins Online has been updated and completed (with the exception of some typos or missing type/subtype records we might invariably find). There are now 2,519 total coin types from Seleucus I until late Roman Republican and early Augustan types issued with under the stated authority of Philip I (posthumously). There are about 6,000 subtypes nested hierarchically under these parent types, and more than 2,000 physical specimens from the ANS, Berlin, Muenster, Harvard Art Museums, and the Fralin Museum of Art at the University of Virginia have been linked to SCO, either at a higher parent type level (for worn coins) or at the specific subtype when an accurate identification can be made. Oliver Hoover is still working on cataloging later Seleucid coins in the ANS collection, so the coverage will be expanded in the near future.

Seleucid tetradrachms

Since the browse page is built logically around parent type numbers rather than the original version of SCO, which was not ordered hierarchically, the images displayed to the right of the descriptive summary include both parent and subtype specimens. As a result, the photographic coverage of parent types is enhanced. At present about 25% of all Seleucid types have at least one physical specimen (which is almost certainly photographed, since our NEH-funded Hellenistic Royal Coinages project has funding to catalog and photograph our entire Seleucid collection). To reiterate: we still have more cataloging work to do for the later Seleucid coinage. The photographic coverage can be derived from a SPARQL query of

This project, along with PELLA and the impending Ptolemaic Coins Online, should prove to be a valuable resource for Hellenistic numismatics to students, scholars, general hobbyists, and archaeologists and museum professionals in aid of identifying and cataloging specimens from museums or excavations.

Geographic distribution of Seleucid coinage from East Greece to Ai Khanoum.

Thursday, October 4, 2018

Linking uncertain mints to probable matches in Nomisma

We have formalized a new extension to the data model to link identifiable mints whose geographic location is uncertain to the Nomisma URI for the place most likely to have been the production site for the mint. Usually, when a mint is unknown, we simply assign the URI to the nmo:hasMint property in the Nomisma ontology, but several type corpora do contain lists of distinct "uncertain" mints. For example, the Republican mints of Sicily 1 and Sicily 2 have been attributed by Michael Crawford in Roman Republican Coinage (1974).

With the publication of Seleucid Coins Online last December and the impending publication of Ptolemaic Coins Online this fall, we have already or will have created more than 100 additional "uncertain" mints. In many cases, we can use skos:broader to link to a parent region, as the region is usually known to a reasonably high degree of certainty. In some cases, the place can be attributed as "probable", and for research and visualization purposes, it is useful to be able to capture this relationship.

Since skos:related has not been used in Nomisma to link loosely related concepts internally, we have adopted this property to generate a blank node that carries two further properties: the rdf:value that is the URI of the mint and an un:hasUncertainty of nm:uncertain_value, which is used rather generally throughout Nomisma RDF. In theory, we can expand the number of instances of un:Uncertainty to handle various gradations of certainty/uncertainty.

nm:uncertain_52_sco a nmo:Mint,
        skos:Concept ;
    dcterms:isPartOf nm:greek_numismatics ;
    dcterms:source nm:seleucid_coins_online ;
    skos:broader nm:mesopotamia ;
    skos:changeNote <> ;
    skos:definition "Uncertain Mint 52, perhaps a Subsidiary of Seleucia on the Tigris"@en ;
    skos:inScheme nm: ;
    skos:prefLabel "Uncertain Mint 52"@en ;
    skos:related [ un:hasUncertainty nm:uncertain_value ;
            rdf:value nm:seleuceia_ad_tigrim ] ;
    skos:scopeNote "This concept should be used only in the context of Seleucid coinage."@en .

In addition to this, we now make it possible to link an attributable workshop to the broader concept of the mint within its field of numismatics. In Seleucid coinage, for example, there are two distinct workshops of Babylon, Babylon I and II. Both of these mints link to nm:babylon as a skos:broader. In these cases, as with the uncertain mints, the RDF for these concepts does not contain specific geographic coordinates, but it is possible to extract them via SPARQL or other API calls.

On the user interface side of things, Numishare has been updated to extract the coordinates from parent or related mints and include them in various geographic data serializations, like KML and GeoJSON. Uncertain mints are styled in gray to differentiate from the usual blue color.

See for example.

Wednesday, October 3, 2018

Major data model update: provenance

At long last, we have implemented provenance directly within the RDF data model. This is something the scientific committee has discussed for some time, and finally implemented. This was no easy task, as it meant reverse engineering the entire editing history from the Nomisma data Github repository in order to establish a chronology of creation dates and significant modifications to the content of the SKOS concepts.

The provenance is encoded primarily in the W3C Provenance Ontology. Each concept now bears a skos:changeNote that points to a dcterms:ProvenanceStatement. This ProvenanceStatement includes a prov:wasGeneratedBy activity for the date of creation and zero or more prov:activity properties that indicate subsequent modifications. Each activity has a timestamp derived from the Github commit history.

When possible, each activity also includes a prov:wasAssociatedWith property that links to a URI in the new namespace. Any Nomisma ID created at the time of the first Github commit was presumed to have been created by Andy Meadows and/or Sebastian Heath, but it becomes complicated after this. Many IDs minted since August 2015 have been generated by a spreadsheet import mechanism. It is important to be able to link a concept to a Google spreadsheet that created or modified it. We therefore use prov:used to link to the public HTML version of the spreadsheet, and we also include some basic metadata about the spreadsheet (the URIs of the Nomisma editors that contributed to its creation, the description of the spreadsheet, etc.). Try a DESCRIBE SPARQL query for the URI,, for example.

By collating the Github commit history with all of the known spreadsheet imports, we have been able to link thousands of concepts to a few dozen spreadsheet uploads. Other groups of manually-created IDs in several categories have been attributed to known editors: Medieval and Modern German IDs to Karsten Dahmen and Walter Bloom; Byzantine rulers to Dennis Mathie. This reverse engineering of all of the Nomisma IDs took about two weeks, and further modification of the Nomisma framework codebase was undertaken to update the HTML output to display provenance, and the back-end editor and import XForms apps had to be modified to accommodate the creation and updating of provenance events.

Here's an example of an ID created on or before 2012 and subsequently updated by two different spreadsheets:

<> a dcterms:ProvenanceStatement ;
    prov:activity [ a prov:Activity,
                prov:Modify ;
            dcterms:type "spreadsheet" ;
            prov:atTime "2015-10-24T04:00:03+00:00"^^xsd:dateTime ;
            prov:used <> ;
            prov:wasAssociatedWith <> ],
        [ a prov:Activity,
                prov:Modify ;
            dcterms:type "spreadsheet" ;
            prov:atTime "2015-08-26T04:00:03+00:00"^^xsd:dateTime ;
            prov:used <> ;
            prov:wasAssociatedWith <> ] ;
    prov:wasGeneratedBy [ a prov:Activity,
                prov:Create ;
            dcterms:description "This is among the original Nomisma XHTML+RDFa fragments, most likely created between 2010-2012 by Sebastian Heath and/or Andy Meadows."@en ;
            dcterms:type "manual" ;
            prov:atTime "2012-10-28T21:43:36+00:00"^^xsd:dateTime ;
            prov:wasAssociatedWith <>,
                <> ] ;
    foaf:topic nm:seleuceia_ad_tigrim .

Importantly, since editor URIs are stored for individual manually-edited events as well as creators/contributors to the spreadsheets themselves, it is possible to execute a SPARQL query to extract a list of a Nomisma IDs created or modified by an individual contributor to the project. By connecting an editor to their ORCID URI in the underlying editor RDF (see, we will be able to generate a DOI that reflects the intellectual contribution of that person to the field of numismatics, and that DOI (as a dataset) will appear on the ORCID profile of a scholar in the same manner as a traditional printed journal article or monograph. This will be an important advancement for Nomisma that I hope might serve as a proof of concept for other Digital Humanities projects.

Improving consistency in TTL and JSON-LD output from Nomisma

In preparation of a new and improved data model for capturing the provenance of data within the Linked Open Data ecosystem (more on that later as I move these updates into production), I have revisited the RDF Turtle and JSON-LD exports from Nomisma.

The new model for provenance, as well as a new method of linking URIs that reflect uncertain mints that may be attributed to known places for Hellenistic Royal Coinages (see will include some blank nodes. It isn't necessary to assign a permanent, addressable URI to every possible modification event for a SKOS Concept. The Provenance Statement (dcterms) has a fragment identifier, but individual activities do not.

Up to this point, the Turtle and JSON-LD serializations from Nomisma were executed via XSLT transformation from the canonical RDF/XML data (which does follow a standard model, as these are generated via controlled processes in the XForms engine). However, the complexity of dealing with blank nodes was not handled in the XSLT stylesheets for these alternative serializations, and so I sought to outsource this transformation process to the Python RDFLib library and its JSON-LD plugin.

Getting this working through Orbeon's XML Pipeline system was a little bit tricky. Orbeon has long had a processor for executing scripts on the command line (execute-processor), but it is not well documented. After a morning of trial and error, I have managed to successfully implement the Turtle and JSON-LD transformations through RDFLib.

The config for the processor is generated by XSLT that reads the URL path structure from the HTTP request headers in order to ascertain that Nomisma ID and Concept Scheme, which is then passed to the Python script as part of the absolute path for the RDF/XML file, which is then serialized into the format of choice.

The XPL file for the JSON-LD transformation is here.

And the simple Python script also in the Nomisma Github folder, under 'script'.

#!/usr/bin/env python
import sys
from rdflib import Graph, plugin
from rdflib.serializer import Serializer

#get argument
id = sys.argv[1]
scheme = sys.argv[2]
file = "file:///usr/local/projects/nomisma-data/" + scheme + "/" + id + ".rdf"

graph = Graph()

graph.parse(file, format='application/rdf+xml')
print(graph.serialize(format='json-ld', indent=4))

Friday, August 24, 2018

University of Passau becomes the 30th OCRE contributor

The University of Passau coin cabinet has joined Nomisma through the NUMiD network of German university museums. It is providing data for 70 Roman Imperial coins in its collection, becoming the 30th contributor to Online Coins of the Roman Empire.

One Passau example Antoninus Pius 771

Monday, August 13, 2018

University of Marburg joins Nomisma

The latest member of the German NUMiD consortium of university coin collections has been integrated into the Linked Ancient World Data Cloud: The Numismatic Collection of the Archaeological Seminar of the Philipps-Universität Marburg. The University of Marburg's contribution of 23 coins spans four type corpora in the Roman and Hellenistic domains: OCRE, CRRO, PELLA, and Seleucid Coins Online.

SCO 1429 is a great example of the research value of these projects and the possibilities that arise as a result of collaboration between large and small numismatic collections. There are are two physical specimens of this coin type: one housed at the ANS and the other in Marburg. Together (and with other eventual additions), these specimens will help form a more complete picture of this typology by facilitating more accurate analyses of measurements and geographical distribution.

Wednesday, August 8, 2018

University of Halle joins Nomisma

The Martin-Luther-Universit Halle-Wittenberg is the latest member of the NUMiD consortium of German university museums (powered by the software framework developed at the Berlin cabinet) to enter the collaborative. Halle is providing access to one Republican and 45 Imperial Roman coins, with more to be cataloged in the future.

One such example can be found in RIC Caligula 56, a coin type that shows a particularly diverse range of data partners: 50 specimens across 8 collections.

Tuesday, July 31, 2018

Numishare now supports JSON-LD serialization for objects

After a few days of work, I have a functional first draft of a reasonably robust JSON-LD serialization for physical objects published in the Numishare platform that conforms to the data model. I have pushed these changes into our production server, and you will have access to this new export format in both the ANS collection, Mantis, and the Egyptian National Library collection.

The export is currently available as a direct serialization of the canonical NUDS/XML published by Numishare, but I will expand the support to include proposed search APIs once they have been fully documented. You can access these serializations either by appending ?profile=linkedart to the .jsonld URL (e.g., or by using profile=\"\" in conjunction with application/ld+json in the Accept header via content negotiation. (I am not sure this is the formal profile URI yet, so I may update this later).

Not all of our data have made it into this iteration of the export. It includes titles and accession numbers, typological metadata like material, typological classification,  production event, and legends and visual iconography that appears on the obverse and reverse (but not complex issues like symbols and their placement), basic measurement data (axis, weight, diamter), and lastly, digital images, including IIIF resources. We haven't included provenance or other sorts of physical peculiarities (secondary treatments, wear, etc.).

A Note on Data Quality

Like all of the objects in the ANS collection, the best quality data are in the Roman department or Hellenistic coinage that has been connected to online type corpora such as OCRE or PELLA. The output only includes entities that have been linked to Nomisma URIs--materials, denominations, authorities, places, and people or deities depicted on the obverse or reverse of coins.

This stater of Philip III Arrhidaeus is linked to a coin type defined in PELLA. The typological metadata are not actually stored in the NUDS record in Mantis itself, but Numishare requests the machine readable data directly from PELLA. Numishare then reads all of the Nomisma URIs from this typological data to make an API request to in order to get RDF for each skos:Concept related to the coin type. The XSLT that generates this JSON-LD from NUDS will look for and use a Getty vocabulary URI stored as skos:exactMatch or skos:closeMatch in Nomisma. If none is available, then the JSON-LD will use the Nomisma URI instead.

Snippet of JSON-LD

As you can see in the above figure, the ULAN URI for Philip III Arrhidaeus has not been resolved, because it doesn't exist in Nomisma's RDF because it hasn't been minted in ULAN. Abydus and Gold, however, do exist in TGN and AAT, respectively, and have already been coreferenced within

So while Hellenistic and Roman Republican/Imperial coinage are the most likely to be fully robust and integrated with Getty URIs, the vast majority of the ANS collection hasn't been linked to Nomisma-oriented typologies. Hopefully, as we migrate from Filemaker to another platform, we will systematically link all of our other departments to the relevant authority files to facilitate better quality LOD output.

In any case, this is a major step forward in making our materials accessible to a broader audience of researchers and developers within art history.

Monday, July 30, 2018

Leeds University Library publishes 61 Alexanders to PELLA

The Leeds University Library is the newest contributor to the consortium, contributing data for 61 Alexander the Great coins in its collection to PELLA. There are 20,266 Alexanders in PELLA from 15 different institutions.

In related news, Oliver Hoover is putting the final touches on the Seleucid Coins Part II spreadsheet and the first part of the gold and silver coinage of the Ptolemies is nearly ready to go online. Look for the fully-published Seleucid Coins Online and the first iteration of Ptolemaic Coins Online by the end of August.

Wednesday, July 18, 2018

Pagination of physical specimens and CSV downloads

I have made some minor modifications to the coin type pages in OCRE, CRRO, etc. A relatively small number of types across these corpora have more than 100 total specimens, but more importantly a very small handful of types are linked to several hundred or even more than 1,000(!) physical specimens. For example RIC 10 Honorius 1228 is associtaed with 2,396 physical specimens, nearly all of which are in the British Museum (presumably from one or more hoards). This is the single-largest number of specimens associated with a coin type. In these extreme cases, the amount of data to load into one HTML page is simply too great, resulting in the browser overloading and running out of memory.

In order to ameliorate this issue, I have introduced pagination. The number of results per page can be set in the Numishare config, but the default is 48 (16 rows of 3 columns). The page is set by a page request parameter, which is converted into a proper offset in the underlying SPARQL query. The pagination buttons, then, are crawlable by robots since each hyperlink will resolve to a URL (so no AJAX here).

Nearly 400 total coin type URIs have more than 48 specimens (out of roughly 55-60,000 total Hellenistic or Roman coin types across all projects) for which pagination controls will appear. About 100 types have more than 100 specimens and 5 have more than 1,000.

In addition, when physical specimens are present, the user can click to download a CSV file for the metadata about these specimens. It is the same basic query that populates the HTML page and includes URIs for each object, title, measurement data, URLs to images or IIIF services, findspot/hoard data, and source collection/dataset. This should make it easier to use coin type and specimen data for analysis in R or other platforms.

Friday, April 27, 2018

OpenRefine workshop materials for ECFN/Nomisma

Next week is the 7th annual European Coin Find Network and meeting in Valencia. I'll be guiding two brief, 30 minute introductory workshops in OpenRefine aimed at cleaning numismatic data and linking to Roman imperial coin type URIs defined in OCRE. I plan to write up the steps in the tutorial at some point, but the test materials can be accessed here:
Expect updates to this post when the workflow I intend to show in the workshop is codified into a written tutorial

Improving OCRE OpenRefine reconciliation with regex

I have made a slight update to improve the matching of OCRE coin types through the Numishare type-based OpenRefine reconciliation API. The reconciliation API queries the "title" as indexed as a text field in Solr, which as detailed in a previous blog post, functions most accurately when you reduce your reconciliation column down to the RIC number and use authority/mint/denomination as an additional property.

This would miss a lot of potential attributions of numbered subtypes that were never given parent type URIs in OCRE. Some examples are in Hadrianic types. The British Museum has assigned the type number '14', but OCRE has no Hadrian 14, only 14a and 14c. The API update appends the following regex to the title field Solr search: '(\(?[a-zA-z]\)?)?', resulting in the query "title_text:/14(\(?[a-zA-z]\)?)?/". This looks for a single lower-case or upper-case optional letter that may optionally be enclosed in parentheses.

When running the API against more than 2000 coins of Hadrian from Rome from the British Museum, about 500 had a 100% automatic match, and another 1,500 yielded two or more potential matches. Before this regex tweak, a significant portion of the 1,500 coins that didn't automatically match had no suggestions, and therefore required the "Search for Match" function to manually attempt through autosuggest by typing with the keyboard.

Friday, April 20, 2018

New updates from KENOM, Münzkabinett Berlin

Two new collection URIs have been minted in for the KENOM project, and the OAI-PMH feed from KENOM has been re-harvested. Now there are more than 7,500 coins (and medals) contributed from that project, including 1 medal from Munich and 4 from Moritzburg for Art of Devastation, a corpus of World War I medals. These medals represent the first partner contributions to AoD, which to this point has consisted only of the American Numismatic Society's own collection.

The updates include 3 coins from Munich for Seleucid Coins Online.

Furthermore, a new update has been run on Berlin's contribution to Online Coins of the Roman Empire, which now includes some coins of the Gallic Empire. With these most recent updates from Berlin and KENOM, there are now 114,136 coins in OCRE.

Thursday, February 1, 2018

A Closer Look at ResearchSpace.

Following on my earlier post about the British Museum's URIs getting killed by the deployment of ResearchSpace into production...

The first glimpse I saw of ResearchSpace was at the Linked Ancient World Data Institute in May 2012. We are fast approaching six years since the first demo I saw, and the project must have existed for at least a year before that. So we are at 6-7 years of development with $1-2million from the Mellon Foundation for an application ( that looks wholly underdeveloped compared to many cultural heritage platforms that I've seen (that were built in a fraction of the time with a fraction of the money).
Let's take a look, shall we?

Um, okay. Not the easiest starting point for a query interface of a museum collection. The interface eschews keyword search--this is a feature, not a bug, mind you (see

Essentially, you can only query by making relationships between different categories of information. If I just want to see the coins of Antioch, I have to sort my way through several iterations of expressing a query as triples. Now certainly there is some potential in querying in this way, but the problem is that this isn't how the vast majority of the public (general public or researchers interested in a specific portion of the collection) expects or wants to interact with the collection through a UI. Libraries, archives, and museums have been implementing faceted search of their collections (based on Solr, ElasticSearch, etc.) for over a decade now. There are facets in ResearchSpace, although they are not prominently displayed (click on the left to show via Javascript). Not all of the facets are terribly useful (some are 1:1 directly with the coin itself with regard to production events), but you do have to have some idea about how relationships are expressed between objects and concepts. I should also note that I'm skeptical that SPARQL-generated dynamic facets will be able to bear the load of production usage.

Okay, I got Things from Antioch. How to narrow? Add another query parameter. How about a Thing that is a Concept. What concept? Well, I have to select the relationship between the Thing and the Concept. "Has type". Useful to be familiar with modeling data in CIDOC CRM before you use the interface. Then I select "coin."

Oh. 0 results? There were definitely coins in the last page.

As it turns out, I really wanted things from Antiochia ad Orontem, but I also need to know that the emperor is expressed by the "refers to" property. "Refers to" appears twice, so you have to select the one with the person icon. There are times when the top-level filters conflict over overlap with the left-hand facets.

Coins of Antioch

User interface issues aside--certainly there is room for improvement here--the larger issue is the time frame and money it cost to arrive with this product. Having been funded by the Mellon Foundation, it would seem that both the data and the code should be open source, but the ResearchSpace code has never been opened, and therefore it is presently impossible to test, critique, or contribute back in order to make the platform better.

Aside from the fact that URIs don't dereference (failing the primary requirement of a LOD system), the UI is entirely driven by AJAX, making it complicated to paginate (clicking on a coin and then clicking back in the browser wipes out your facets and your page number) and impossible for a robot to crawl the collection, thus reducing access to the public who might happen upon museum objects through search engines. At the ANS, about 70% of all visitors to our Library, Archive, and Museum platforms come through search engines.

Even if you go to , what is actually there? A CURL yields the same basic HTML template. There's actually no useful information for a machine to extract--not even human readable versions of the data--and especially not RDFa or other types of microdata.

Content negotiation?

curl -H "Accept: application/rdf+xml"

No response. No HTML header metadata pointing to alternative serializations that can be requested by URLs. The whole system is antithetical to modern design--not just within cultural heritage, but everywhere.

ResearchSpace project managers have traveled from conference to conference in digital cultural heritage over the years, talking about the system and its advanced functionality, but the product we are seeing now falls extremely short of the hype. The problem has been in its management. It seems, from the outside, that there were never any achievable goals that could be reached in a concrete timeline. The ambition for the project grew to include IIIF, 3D annotation, and a host of other useful features.  ResearchSpace shot for the moon for its first public release. However, the project could have been released as a simpler framework years ago with these new features added in iterative development. With the code stored in Github, they might have been able solicit feedback from the cultural heritage community. Is ResearchSpace writing its own IIIF viewer? WebGL viewer? Is it using other open source libraries? Who knows.

There are a some cool features in the system--distribution analysis of categories based on your queried subset.

Material distribution of Antiochene coins of Elagabalus

So there's obviously potential. But between the high cost, the long duration of development, and the application architecture itself, with its walk back from stable URIs and REST, at what point is it safe to question whether or not the project has been a success? (since it technically exists on the web now, I suppose it's no longer vaporware) Did the British Museum lay off Dan Pett and put all of its eggs into the ResearchSpace basket for its future online collection database? It's really a crying shame that the BM employed one of the 10 top thinkers and doers in Digital Humanities in the entire world--the one person in their organization with the experience and creativity that might have been able to salvage the BM online collection and do something truly revolutionary with it (as he had done with the Portable Antiquities Scheme). It's a completely squandered opportunity, and the BM has done much to destroy the reputation it has gained as a leader within the museum Open Access and Open Data movement.

On stable URIs at the British Museum

Update, 2 Feburary 2018: The previous iteration of (Metaphacts) has been restored, and the collection object URIs now redirect once again to the Metaphacts framework. Earlier critiques of the system design still stand, relating to referenceable URIs, CURL, content negotiation, etc.

There are 61,853 coins from the British Museum integrated into's SPARQL endpoint and made available through type corpora such as OCRE and CRRO. The BM is the single largest contributor of numismatic data, providing about 3,000 more coins than the American Numismatic Society itself. With the aid of its highly talented and collaborative curators in the Coins and Medals Department, the British Museum's contributions to this research ecosystem have been transformative for the discipline, and the BM has played a vital role in demonstrating, through Linked Open Data methodologies, that LOD makes the whole greater than the sum of its parts.

This morning, all links have died.

And not died in the way that they have died when the oft-neglected, but extremely valuable (even though it had some obvious data modeling problems) British Museum SPARQL endpoint has gone down. Now they are 404's. Dead. Gone. Not a spinning circle you get when a server application runs out of memory. We've all known that there's some wonky and inefficient CIDOC-CRM modeling, and despite claims from ResearchSpace project managers, the British Museum data were never 5* Linked Open Data because they never linked externally. But stable, clean URIs are the A #1 requirement for LOD architecture.

And so ResearchSpace has managed to kill their own URIs when transitioning to the public version of the software. I was assured many years ago that these were the permanent URIs for objects.

So the URI for this coin of Augustus is dead:

However, you can still access the data in the new ResearchSpace system at

It should be noted: The BM implemented https://, effectively changing the URIs of its objects, but the URIs within the underlying graph database/SPARQL endpoint are still http://.

But you shouldn't have to negotiate the ResearchSpace framework with an unclean, application-specific request parameter to extract the data for At least create a proxy that allows for the resolution of the URI into human and machine-readable data, as per Linked Open Data principles? Or a semantic 303 redirect? Anything but straight-up killing millions of URIs. This betrays a serious deficiency in how to develop web applications.

Wednesday, January 17, 2018

Nearly 2,000 Roman Imperial coins from the University of Graz integrated into Nomisma

After several weeks of working with Elisabeth Steiner at the University of Graz, a large portion of the collection of Roman coins at the Institute of Ancient History and Classical Antiquities has been integrated into the SPARQL endpoint and is available in OCRE and CRRO. About 300 Republican coins were initially ingested in October, but the coverage has extended by nearly 2,000 coins from the Imperial period. The collection includes images published according to the IIIF specification, which is rapidly becoming the standard API by which new partners make their images available online. Unlike most Nomisma contributors, where intermediary harvesting scripts transform source XML or CSV into Nomisma-compliant RDF, the University of Graz export is a direct serialization of TEI from their Fedora repository into RDF.

An antoninianus of Gordian III at the University of Graz

What's especially notable about this collection is that it was a successful demonstration of the new Numishare and OpenRefine reconciliation APIs for normalizing RIC references to OCRE URIs. The first step was to normalize mints, emperors, and denominations to Nomisma preferred labels, which were then used as additional property search parameters for normalizing the RIC numbers themselves to the relevant OCRE URI.

You can read more at:
These new reconciliation APIs are the topic of my CAA presentation and paper in two months in the tools session.

Wednesday, January 3, 2018

Fralin Museum coin collection leaps forward, embraces IIIF

The Fralin Museum at the University of Virginia numismatic collection has received a major functional update thanks to collaboration with the Libary's Information Technology group (particularly, Mike Durbin). The data and images at long last have been migrated into the university's institutional repository--the data have been updated to conform to the latest version of the NUDS schema (with TEI namespaced for bibliographic references) and the images are now available through IIIF web services. I have updated the record page code to use the Leaflet IIIF plugin, so all high resolution images are zoomable now.

Tetrachrachm of Antiochus available in SCO. 1990.18.8

As such, the IIIF service metadata are exposed in the RDF that is harvested into the SPARQL endpoint (according to the Europeana Data Model spec), and the zoomable images are available in OCRE, CRRO, PELLA, and now, Seleucid Coins Online, for which the Fralin has contributed one coin of Antiochus I thus far.

In total, 427 coins in the museum (more than 80%) are hooked into the broader ancient world linked data cloud, available not only through numismatic linked data systems, but also broader aggregations of ancient world materials from Pelagios Commons, to which the Fralin has contributed since at least 2012 or 2013.

A zoomable Fralin aureus of Hadrian displayed in OCRE.

As Seleucid and Ptolemaic Coins Online expand in the next few years as part of the broader NEH-funded Hellenistic Royal Coinages project, more Hellenistic coins from the Fralin will be linked in and made available to students and scholars of numismatics. Although the Fralin's collection is so small that no numismatist would travel there to conduct research (unlike the major collections of the American Numismatic Society and the British Museum), these coins and others from small university and civic museums can be made available for research, filling in gaps between larger collections and painting a more complete picture of the circulation of ancient coinage. Indeed, one of the Fralin's aurei of Trajan (a reissue of Tiberius) is unique among all collections contributing to OCRE, now totally 110,000 objects (RIC Trajan 821).

Other Updates

The version of Numishare running on the Scholars' Lab server is circa spring 2013, predating the migrating from the now-defunct Apache Cocoon to Orbeon. There's virtually no way of testing code changes locally, and so I had to roll the dice on very minor updates on the Scholars' Lab test server. These updates included the implementation of the Leaflet IIIF libraries, as well as some minor changes to the map function to fix a glitch with deprecated URLs for the Digital Atlas of the Roman Empire's Imperium Romanum baselayer in OpenLayers. I also replaced the Google Maps physical layer with one published by Mapbox. I'd migrate from OpenLayers to Leaflet entirely, but ideally, the entire platform should be migrated to the current version of Numishare.

A link to the record in Virgo (the online library catalog) has also been added into the record. This URI is stored within the NUDS control as an otherRecordId[@semantic='rdfs:seeAlso'], and therefore comes through in the RDF in the rdfs:seeAlso property.

University of Freiburg joins Nomisma

The coin cabinet of the Albert-Ludwigs-Universität Freiburg is the latest member of the NUMiD consortium to join the Nomisma project and make its coins available through OCRE and CRRO. The number of cataloged specimens made available in OCRE and CRRO stands at 100 so far, but this comprises only a small portion of the total collection of more than 12,000 objects.

About the collection:
The Seminar of Ancient History holds more than 12,000 coins of the Roman Imperial period and Late Antiquity. Their majority originates from a collection which Herbert Nesselhaus, the former Professor of Ancient History, was able to purchase in 1961 from the Archbishopric of Freiburg. The collection had found a temporary home there some twenty years earlier: Between 1900 and 1926 the Geheimer Oberbaurat Heinrich Wefels from Erlangen built a collection of c. 14,000 coins, which he had acquired at various auctions. About 10,300 are coins of Roman emperors and an additional 2,400 represent provincial issues. Wefels focussed on the Imperial period, but did add both earlier and later coinages, too. About 950 Byzantine coins, 360 Roman Republican ones, 220 Greek issues, and 22 Celic coins bear witness to these secondary areas of interest. Although the Seminar für Alte Geschichte is not any longer able to purchase additional coins, its collection was augmented through generous donations by Herbert A. Cahn, Otto Feld and Gerold Walser. Today the collection is complemented by a scientific numismatic library, which again originates in the collector Heinrich Wefels.

 An example coin can be found at Augustus 252.