The Portable Antiquities of the Netherlands (PAN) portal and the data model behind the description of the findings are discussed in detail, and how this approach leads to publishing data that is FAIR .

1. Archaeological small finds from field to file
Citizen science approach and data structure of the PAN-project
dr. S. Heeren (VU, Amsterdam) 17 March 2020 SEADDA, Leiden, National Museum of Antiquities

2. Background PAN
• Private metal detection since 1970s
• Estimated number of 2500 important
collections, c. 200.000 metal items from
prehistory until Late Middle Ages
• Not yet systematically studied
• Problematic relation between private finders
and professional archaeologists

3. A change in legislation
• Pre 2016 situation: illegal but tolerated
• Chance finds to be reported to Minister/Mayor
• No central reporting desk: Archis, NUMIS, regional archaeologists….
• National Archis database unfit for private persons reporting their finds
• Very limited amount of find reports
• New Heritage Act July 2016
• 30 cm topsoil can be metal detected
• Monuments and excavations excluded
• Some municipalities can set limitations (APV)
• Permission from the landowner
• Obligation to report all finds
• Ownership:
• single finds for finders
• hoard finds shared between finder and landowner
• province claims illegal finds

4. Why PAN?
Research potential
Nauheim brooch, c. 150 – 70 BC
Nauheim
50 km0

5. Why PAN?
Research potential
Nauheim brooch, ca. 150 – 70 BC
Research Heeren/Van der Feijst 2017, plus published
data J. Werner (1955), M. Feugère (1985)

6. Why PAN?
Research potential
Battlefields: hardly any features; skeletal remains rare. Metal artefacts remain

7. Why PAN?
• Collections have a huge research potential:
• Distribution maps Trade networks, habitational patterns, human mobility, etc.
• Site types that are hardly found by traditional archaeological research
• Societal importance: participation of the public, citizen science
Why in 2016?
• Sense of urgency. Preventing dramatic loss of information
• The new Heritage Act (Erfgoedwet) 2016.

8. Aims of the PAN project
• Systematic documentation of private collections archaeological finds
• Make finds available for science and heritage research & the broader public
• Via online publication in a durable database (Linked Open Data)
• Improve relation between professionals and private searchers
• International cooperation in these fields

9. PAN national network
• associations of hobby-archaeologists
• individual metal detectorists
• several universities
• National Heritage Agency (RCE)
• Nederlandsche Bank (NUMIS coin database)
• DANS-EASY: backup & European portals
• several provinces
• museums
• small companies & detector websites
• Digital partner: Geodienst (RuGroningen)

10. Project setup
Initial grant by NWO
• Investment fund large infrastructure
Setup phase 1 (2016-2020) (2.3 m)
• 8 Finds Liaison Officers
• 3 Finds Specialists
• Software developers
• Project management
Development phase 2 (2020 – 2022) (0.6m)
• Continuation, Phase 2: maritime collections
• More attention for volunteers, outreach and
communication of results
2022: full adoption by RCE

11. Citizen Science
• Academia accountable to society: ‘democratisation of science’
• Share Open Access
• Explain ‘Valorisation’ / outreach
• Participation Professionals no monopoly on research – Citizen Science
• History / archeology / museums / heritage
• ‘Who owns the past’?
• Non-professional researchers are entitled to study the (material) past
• Human Rights article 27 Unesco 1952
• Malta (La Valletta) 1992: professionalisation!
• Faro 2005: more attention for participation.
• Participatory governance, participatory heritage

12. Citizen science
1. Citizens actively involved 2. Genuine science outcome
3a. Participation advantage for the citizen scientists 3b. Participation advantage for the scientist
4. Citizen scientist may take part in various stages 6. Citizens science is considered approach as any other
5. Citizen scientist receive feedback from the project (limits and biases considered)
7. Data and meta-data available, preferably Open Access 9. Citizen science programmes are evaluated
8. Citizen scientists acknowledged in results and publications 10. Leaders of citizen science projects consider legal
and ethical aspects
Involvement Good science
European Citizen Science Association
https://ecsa.citizen-science.net/documents

13. Working with the public
• Roles for private individuals in PAN
• Declaring their finds
• After training:
register finds from other owners
• Knowledge: assist in find
identification (esp. period
after 1600)

14. Working with the public
Findspots entered as precise as possible
- old find: parcel
- new find: exact co-ordinate
 dec. 2019: mobile app with GPS
Online presentation by municipality

15. Working with the public
Outreach methods:
• PAN-site reserved for data entering & presentation
• Facebook used for news and contacts
• Articles in detector magazines, as well as in popular -scientific magazines
• Presence at detector rallies and events, distribute flyers

16. Working with the public
• Unrealistic expectations; social media small uproar
• Quick processing
• Complete coverage
• Illegal behaviour by minority
• Looting of scheduled monument sites
• No permission of landowner
• Selling of undocumented artefacts
• Whitewashing (illegal/bought objects on other location)
• …
• Our approach
• Work together with organizations and willing individuals
• Use traditional and new media for attention, including regulation
• Booklet code of conduct: Gedragscode en regelgeving rondom metaaldetectie

17. Control excavations by PAN and RCE
• Reservation of a budget for small control excavations by PAN and RCE in case
of exceptional finds reported by metal detector users.
• Aim is to check the find reports and acquire additional context information.
• Excavations generate media attention which enables us to promote correct
behavior by metal detector users – and it signals that we take them seriously

18. Current state of PAN (1 March 2020)
• Documenting finds started 3,5 years ago (1 Oct. 2016)
• 752 searchers
• 7.206 locations
• 68.664 records registrered
• 78 hoard finds
• 31.394 available online (46%)
• Difference registered / online:
filling the reference collection

19. Photo’s
Measurements
Material
Private/museum
Other data
Label
Dating
Scope notes
Definitions
References
Links
Finds
in PAN

20. Projectiles
Schoes
Writing equipment
Jewellery
armring
brooch
finger ring
20

21. 21

22. Reference collection – tree structure
Function Jewellery
Object Armring
Armring metal
Open armring
Open armring with terminal knobs
Open armring with continuous knobs
alt. label: ‘type Wessem’

23. Connection to other thesauri
Mapping of all reference types to
• Dutch Archaeological Basic Register update (ABR+)
• Getty Art & Architecture Thesaurus (AAT)
• ….
SKOS-based (Simple Knowledge Ordering System) in ‘triples’
• [term A]….IsExactMatchTo….=[term B]
• [term E]….IsNarrowerMatchTo….=[term F]
• [term K]….IsBroaderMatchTo….=[term L]
Examples
• When describing ‘situla’, link it to ‘bucket’ as broader concept
• When describing ‘Wire brooch Almgren 15’ link it to ‘brooches’ as broader concept
• Using Getty AAT semantic links: http://vocab.getty.edu/aat/300045995 = ‘brooches’
Search engines such as Ariadne will navigate using Getty AAT
All systems linked to Ariadne will have to use SKOS-mapping of their terms to Getty AAT

24. In practice: Poolparty Semantic software package

25. In practice: Poolparty Semantic software package
pins (jewelry) – Getty AAT
hairpins - GettyAAT
haarnaald – ABR+

26. In practice: Poolparty Semantic software package

27. PAN contains the objects
and
…draws on the content of PPSS for
the reference type data
Reference collection ref.data from PoolPartyPAN database

28. Identification of finds
Visual recognition in a tree-structure
Available on the website without login
Authors: professionals and amateurs with
editing process by the PAN-staff
In background linked to other thesauri
Reference collection

29. • A: Registration and publication of Dutch soil finds in private property
• Open Access for all finds; near open (some restrictions) for findspots
• B: Reference collection for archaeological finds
• Open Access: PPSS can be approached via API-server connection
• Bilingual: Dutch and English (other languages possible)
• Objects and ref.coll. separately available via URIs
• Object: https://portable-antiquities.nl/pan/#/object/public/18315
• Ref. type: https://portable-antiquities.nl/pan/#/reference-type/01-04-01-05-03
• Connected to NUMIS and DANS-EASY via automated protocols
• NUMIS: national Coin Cabinet
• DANS: backup and European servers such as Ariadne, possibly Europeana
PAN is…

30. • Findable
• PAN-website
• DANS deposits
• Ariadne links
• Accessible
• PAN-website: levels of access for visitors, collectors, researchers
• Interoperable
• machine to machine: API server for reference types
• Linked Data: pictures, bibliography, reference data in triples
• NUMIS-data connection
• DANS-deposits
• Reusable
• wider public: dowload pictures, view information
• researchers: download / export datasets
PAN is…F A I R

31. • A: Registration and publication of Dutch soil finds in private property
• Open Access for all finds; near open for findspots
• B: Reference collection for archaeological finds
• Open Access: PPSS can be approached via API-server connection
• Bilingual: Dutch and English (other languages possible)
• Objects and ref.coll. separately available via URIs
• Object: https://portable-antiquities.nl/pan/#/object/public/18315
• Ref. type: https://portable-antiquities.nl/pan/#/reference-type/01-04-01-05-03
• Connected to NUMIS and DANS-EASY via automated protocols
• NUMIS: national Coin Cabinet
• DANS: backup and European servers such as Ariadne, possibly Europeana
• FAIR (Findable, Accessible, Interoperable, Reusable)
PAN is…

32. Reference collections
• Identification of finds
• Easy visual recognition
• Available on the website without login
Sort objects by period
Search the map
After login:
• researchers can selects and export datasets
• finders can manage their collection
Public website

33. PAN-website: * finders: document collection
* everyone: simple searching

35. Some exciting results….
• Single objects or object groups
• Interesting distribution patterns

36. Noord-Holland: vondsten
Texel
3 fragments of spectacle brooches, 1000 – 750 BC
PAN-55723, 55722, 51197
Noordwijkerhout – RMO Leiden

37. Bronze Age weapons
Bronze Age Axes
2000-800 BC
Spearheads
(Bronze Age until Early Iron Age)
2000-500 BC

38. Late Iron Age (250-13 BC)
“Celtic” coin, silver ring, many pieces of glass bangles

39. Early / Middle Roman period (1st-3rd century AD)
Brooches, weapons, coins, figurines….

40. Late Roman period
A hairpin type considered rare (until now…..)

41. Medieval swords, deposited in rivers
Gemeente Noord-Beveland PAN-60456
Zwaard van het Ulfberht-type, 11e eeuw

42. Municipality of Middelburg
13th century PAN-42137
Province Zeeland: a rare candlestick

43. 100 years war (16th-century uprising against Spain)
Halberd furket (musket-gun support)

44. Schat van Westwoud, Ca. 1571
Ensemble: PAN-S-00010
(Foto: Archeologie West Friesland)
100 years war (16th-century uprising against Spain)

45. 100 years war (16th-century uprising against Spain)
Coin hoard t.p.q. 1621 – Siege of Breda 1624-1625

46. 100 years war (16th-century uprising against Spain)
Gunpowder horn 1604

47. 16th-17th century
Amsterdam
Tin toys, c. AD 1640
PAN-1876
Album Amicorum of Nicolaas van Zeyst
Date: 1588 KB (National Library)

48. Romano-Frankish contacts
• Echt (2014): 407-411 Lienden (2016): AD 457-461 or a little later
• Payments of Roman emperors to foederati, external auxiliary troops
• Written accounts (451, 455, 463):
• Battle in Rhone-Seine-Marnegebied (Huns, Visigoths, Romans, Franks)
• After burial Childerik in Tournai (481/2) ‘christian’ king Clovis moves to Reims and Paris
• Lienden: Lower Rhine area stays Frankish/Roman recruiting base until at least AD 460

49. Romano-Frankish contacts
• Olst Beilen Velp (H.-K. 1851)
• Neck rings of the Velp type made of smelted solidi or in Roman weight measures
• By ‘barbarians’? Or made in Roman workshops?

50. Sittard-Geleen, Limburg
• PAN-36398 + 36396
• New fragment of a Velp-type neck ring plus solidus-pendant
• New hoard close to another one already known

51. Veere, Walcheren: PAN-10398
• Walcheren: VICTORINVSFVIMB 153 g.

52. Veere, Walcheren: PAN-10398
• Dr. Pieterjan Deckers, VU Brussel / Aarhus Universiteit, Dk
• Neck ring Walcheren compared to Roman, medieval and modern gold
• Platinum to gold platinum to silver gold to silver
• Conclusion
• Composition: gold with fair amount silver used for neck-ring
• Trace-elements deviate from medieval and modern gold: authenticity not in question
• Trace elements good match with monetary gold of period 220-346 nC; other source later

53. Romano-Frankish contacts
• “Fall of Rome” studied for centuries by historians
• Foederati and barbarians play an important role: ‘fall’ supposedly because of
invasions; hiring of external troops is the weakness
However:
• Is the employment of foreign people that novel?
• Are there no Germanic-made objects within the province at an earlier stage?
• Is there no Roman-Germanic contact in the limes zone before?

54. Romano-Germanic contacts
• Johan Nicolay, 2007: Armed Batavians.
• Julius van Roemburg: Unarmed Cananefates?
• Roman (military) horse gear in PAN
• Armed Frisians?!

55. Romano-Germanic contacts
• Brooches of Germanic manufacture in PAN
• Composite brooches ‘with high catch-plate’ (Almgren Gr. VII serie 2), ca. 190 – 270

56. Romano-Germanic contacts
• Germanic brooches in PAN: variant of trumpet-headed brooch
• A. Böhme-Schönberger 1998: Almgren 101 (60 – 160 nC)
• From 3 to 16 specimens

57. Romano-Germanic contacts
• Germanic brooches in PAN
• A. Böhme-Schönberger 1998: Almgren 101 (60 – 160 nC)
• PAN-33552, Zaltbommel
variant Nexenhof

58. Romano-Germanic contacts
• Germanic brooches in PAN
• Almgren 10-13 (Grasselt 1998): period 20 – 80/100
• From 4 to 18 specimens (12 locations)

59. Romano-Germanic contacts
Provisional conclusion:
• Roman made artefacts appear in Germanic area beyond the limes in high numbers
• Germanic made jewelry reach the Roman province in considerable numbers
• Germanic immigration and participation in the Roman province is rather a
constant through ages than a new phenomenon from the Late Roman period
PAN is a powerful tool for new avenues of research
PAN already highly suitable for outreach purposes

60. Visit us: www.portable-antiquities.nl
• Questions?
• PAN in general pan.fgw@vu.nl
• Stijn Heeren s.heeren@vu.nl