, Legend Heading
LegendHeading
Open Ground · Hwy 38, near Philipsburg, MT

Gem Mountain Sapphire Mine

Gem Mountain Sapphire Mine: still unexplained.

◆ Evidence tier: TraditionFee dig · Rock Creek gravels – present◎ Recently discovered — still growing

The Story

What is claimed · what is sourced · what is still disputed

The oldest and largest public sapphire ground in America. You buy gravel by the bucket, wash it at the trough, and tweezer out the rough, blues, greens, the odd orange that heat-treats to fire. Millions of carats have come off Rock Creek since the 1890s, and the gravel has not run out. Neither have the people bent over the trough.

What remains open

  • No period map of the site has surfaced.
  • No contemporary press coverage has been found.

The lure: Montana sapphires in every color but red

Evidence & Corroboration

Distinct evidence classes that independently agree — never a single score

Historical tradition
Newspaper mention
Scholarly support
Archival evidence
Official map/chart
Corroborated
Verified fact

? Open

  • No period map of the site has surfaced.
  • No contemporary press coverage has been found.

Historic Maps

Period cartography · Library of Congress & DPLA via IIIF · deep-zoom

◇ No period cartography on file yet. The IIIF map adapters (Library of Congress, David Rumsey, DPLA) fill this automatically when they find charts of this place.

Period Newspaper Coverage

Dated OCR mentions · Chronicling America / loc.gov — a mention proves circulation, nothing more

◇ No dated newspaper coverage yet. Chronicling America runs against this legend automatically and lands dated clips here.

Archival Documents

Manuscripts, government records, company filings · NARA · IIIF · registries

◇ No archival documents on file yet. NARA and national-archive adapters attach primary records here as they surface.

Timeline

Every event source-backed · unsourced events are dropped, never invented

◇ No dated, source-backed events yet. Timeline entries are built only from evidence with a confirmed date -- nothing is estimated or invented.

Sources & Citations

Typed, first-class citations with retrieval provenance

◇ No typed citations compiled yet -- check Historic Maps, Newspapers, and Archives above as they fill in.

From the archive

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