wariq: Viking-age Baltic silver hoards and Islamic dirhams, machine-readable

Machine-readable data for the tenth-century silver crisis: the collapse of the flow of Islamic dirhams that funded Viking-age northern trade. Two published catalogues, neither of which existed in structured form, extracted and released as CSV and RDF: 548 Viking-age silver hoards from Gotland, Pomerania and Svealand, from Gruszczynski's catalogue (Oxford Research Archive, 2019), with findspots, deposit dates, containers, deposit classes, silver weights and per-hoard coin counts by origin. 394 coins from the web-published volumes of Corpus Nummorum Saeculorum IX-XI (CNS), with striking dates in both AH and AD, mints, dynasties, rulers, weights, diameters and die axes. Two features distinguish this from a plain transcription. The sources' own uncertainty is preserved. Numismatic catalogues record how much of a legend could actually be read, bracketing restored characters mid-word. 29% of mint attributions and 32% of Hijri dates in these volumes carry such a mark. Nearly every digitisation strips it, and the Nomisma RDF ontology has no property for it, though the NUDS XML schema does. Here the printed form is kept alongside the normalised one and the uncertainty is a flag rather than a deletion. Mints are normalised and aligned. A registry folds transliteration variants across scholarly traditions - al-Shash, al-Shash, as-Sas are one mint - and aligns 64 of 77 mints to Nomisma.org URIs. Findspots are resolved to Wikidata entities. Applied to the American Numismatic Society's 17,433 dirhams, the same registry resolves 48.9% of their mint-bearing coins without modification. Every defect found in the data or in the code that produced it is published alongside it, including several that were errors in our own checks rather than in the sources. Cite the catalogues, not this dataset, for the underlying evidence: Gruszczynski (2019) for the hoards, CNS for the coins. This record covers the structured form and the code that produced it. Site: https://calgacus.srht.site/wariq/ Code: git.sr.ht/~calgacus/wariq