Cite this as: Deckers, P. 2025 All the single ladies? Detector finds, dispersed data and suboptimal sources in the study of Viking Age metalwork, Internet Archaeology 68. https://doi.org/10.11141/ia.68.6
In a growing number of countries, the activities of hobby detector users are lauded as a vital source of information about the past. The present paper argues that this statement is not unequivocal. An all too idealist view of the impact of detector finds, and of the recording schemes that capture and publish this data, obscures the laborious process that constitutes the heuristic stages of finds research. As a case study of select types of (pre-)Viking Age metalwork found across multiple northern European countries demonstrates, metalwork data are dispersed across multiple sources, often not conforming to academic standards. This situation complicates the retrieval, validation, processing and publication of information and hampers participation of the interested public. Through the case study analysis, the paper explores the factors contributing to the knowledge potential of detector finds data and the suboptimal sources containing such data. As a conclusion, it provides pointers forward for individual researchers and the discipline at large.
Corresponding author: Pieterjan Deckers
pieterjan.deckers@kuleuven.be
KU Leuven
Figure 1: Examples of the principal classes of artefacts considered here: 'Valkyrie' pendants/mounts class 1, single unarmed woman (a); class 2, single armed woman (b); pendants/mounts depicting hair gripping figures (c); horse-shaped brooches (d); class 3, scene with armed woman and rider (e); brooches depicting a horse and rider (f). (a) Klinta. Gabriel Hildebrand, Historiska museet/SHM; (b) Skodsebølle. National Museum of Denmark; (c), (d), (e) Tissø; National Museum of Denmark/Pia Brejnholt; (f) Birka bj. 825. Christer Åhlin, Historiska museet/SHM. All images CC BY 4.0.
Figure 2: Distribution map of finds in the inventory, grouped by finds location (image by author). Bounding box coordinates: xmin -2.476932, ymin 51.652750, xmax 32.865994, ymax 69.281149
Figure 3: Provenance of finds of all classes considered in this paper, by country (image by author).
Figure 4: Provenance of finds of all classes considered in this paper, by year of first publication (image by author).
Figure 5: Publication status (situation 2020) of metalwork artefacts considered in the case study, by provenance (image by author).
Figure 6a: Nature of the first publication of detector finds of all classes, first published between 2000-2020 or publication date unknown; Figure 6b: Data journeys of all detector finds of all classes, between their first publication and their publication status in 2020 (image by author).
Figure 7: Distribution map of regional subclasses of 'Valkyrie' pendants/mounts class 2 (image by author). Bounding box coordinates: xmin -1.631865, ymin 51.652750, xmax 13.160615, ymax57.861915
Figure 8: Distribution map of regional subclasses of horse-shaped brooches (image by author). Bounding box coordinates: xmin 4.963231, ymin 54.755547, xmax 20.908514, ymax 62.414102
Figure 9: Scatter plot demonstrating the knowledge gained by including detector finds and suboptimal sources within the inventory, differentiated across artefact classes and data sources. ‘Grassroots’ sources are those built and maintained by the hobby community: social media groups and hobbyist resources such as online fora and community databases. A: morphological knowledge (Y-axis reflecting the additional subclasses identified divided by the overall number of subclasses); B: spatial (Y-axis reflecting the number of subclasses for which new spatial information was gained, divided by the overall number of subclasses) (image by author).
Table 1: Overview of source types consulted for this study.
Table 2: A classification of 'Valkyrie' pendants/mounts class 1 and 2 and horse-shaped brooches. For 'Valkyries' class 2, reference is made to the variants defined by Gardeła et al. (2022) where possible.The provenance of the find that allows the definition of the subclass and its source type are indicated if they are detector finds and/or from a suboptimal source.
Table 3: The FAIR principles as originally defined for use with digital datasets, and as adapted to use here in the evaluation of diverse types of archaeological source material.
Table 4: FAIR principles as applied to archaeological artefact data. To aid visual interpretation, the expedient green-red colour scheme offers an impression of higher or lower scores within each of the FAIR criteria (columns).
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