The Colter Stone is the most-famous physical artifact tied to Colter's name, and the cleanest example on the route of how to handle public-interest objects that scholarship does not endorse. We treat it as a curiosity, not evidence. The map and this profile say so.
The Teton Valley (Pierre's Hole) was Shoshone and Bannock country, used seasonally for hunting and as a crossing between drainages. The stone itself — if authentic — would mark a non-Native passage through that country, not its discovery.
If the stone were authentic, it would be a fur-trade artifact: a trapper's mark, scratched into rhyolite during the 1808 traverse. The form (a roughly head-shaped stone) is unusual; the inscription is plausible only if Colter himself carried tools and a motive to leave a mark.
Found 1931 by farmer William Beard while clearing a field outside Tetonia, ID. Rhyolite. Inscribed 'JOHN COLTER' on one face and '1808' on the other (forms vary in reproductions). Acquired by Grand Teton National Park; on loan to the Teton Valley Historical Museum in Driggs.
The stone has never been authenticated. The leading scholarly alternative — argued explicitly by Mattes (NPS, 1962) and others — is that members of the 1877 Hayden Survey planted it as a prank, knowing the country would later be searched for Colter relics. The Mattes treatment is the canonical reference.
Effectively everything. Whether Colter ever held the stone. Whether the inscription is contemporary with 1808 or with 1877. Whether the find spot is meaningful. The stone is a public-curiosity object that the route map carries because the public asks about it — not because the scholarship supports treating it as evidence.
The stone is on display at the Teton Valley Historical Museum in Driggs, ID, on loan from Grand Teton NP. The museum is a small local institution; imagery rights are restricted and require both Teton Valley Historical Museum and GRTE Museum Collections approval. The NPS page on the stone is at home.nps.gov/grte/learn/historyculture/colterstone.htm.
Phase 3, contingent on permissions: photogrammetry of the stone (open-format USDZ + glTF export) co-produced with the Teton Valley Historical Museum.
Sources & attribution: Teton Valley Historical Museum · NPS Grand Teton (loan holder) · Merrill J. Mattes (NPS, 1962) · Teton Valley News, "Colter Stone Exhibit Revamped"