Core catalog
USGS Mineral Resources Data System (MRDS)
Contributes: mine identity, commodities, development status, underground eligibility evidence.
Does not prove: current access, current condition, or independent field verification.
Historical physical features
USGS Prospect and Mine Related Features
Contributes: historical mapped shaft/adit/tunnel symbols (DOI 10.5066/P9TAALR6).
Does not prove: that a feature still exists, or that every nearby symbol belongs to one mine.
California
California DMR Mines Online
Contributes: state operation/status, reclamation, reporting year.
Does not prove: underground workings by itself, or permission to enter.
Nevada
Nevada Bureau of Mines and Geology
Contributes: current/recent operation context, operator, commodity, district metadata.
Does not prove: underground workings or access status.
Nevada Division of Minerals (AML context)
Contributes: program context only. Precise AML opening coordinates are not published for import.
Arizona
Arizona Geological Survey / ADMMR
Contributes: historical mine documents and extracted workings citations when accepted.
Does not prove: current access or open workings. Candidate/possible document matches stay admin-only until accepted.
Access / land management
Official tour operators, foundations, parks, and land-management pages may support access facts when cited on a mine record.
Community
Member verifications, flags, condition reports, and approved mine-relevant photographs after moderation.
Active sources
Mindat
Contributes: independent locality identity confirmation, reported minerals, and — only when the underlying description explicitly documents it — underground workings evidence (shafts, adits, drifts, stopes, and similar).
Does not prove: underground workings on its own. A Mindat locality match does not automatically establish underground workings — Mindat catalogs mineral localities, prospects, claims, quarries, and districts alongside genuine underground mines, so every match is reviewed before it becomes a public source. Mindat photographs are never imported or displayed on this site.
mindat.org · accessed via the official Mindat API, never scraped.