Obsidian (Glass Buttes) — Obsidian (Glass Buttes)
Obsidian (Glass Buttes) blmcalifornia, Wikimedia Commons, Public domain (US)

Material · lithic

Obsidian (Glass Buttes)

North America — Great Basin & Plateau, North America — Pacific Coast

Glass Buttes obsidian comes from a cluster of volcanic buttes in central Oregon that supplied Great Basin and Plateau peoples for over ten thousand years and is the most famous obsidian source in the Northwest. Its many varieties include black, mahogany, rainbow and silver sheen. The source is on public land where modern collecting is allowed by permit, which makes it the favourite material of modern knappers.

Kindlithic
RegionsNorth America — Great Basin & Plateau, North America — Pacific Coast

Sources

The buttes lie in Lake County, Oregon, south of Highway 20 between Bend and Burns, on Bureau of Land Management land with multiple named flows. Cobbles and nodules litter the slopes.

Identification

Glass Buttes obsidian is glassy and translucent to opaque in black, brown, mahogany-and-black, red-and-black, rainbow, gold-sheen and silver-sheen varieties; chemical sourcing by XRF is the only certain identification. Hydration rims develop on ancient surfaces.

Substitutes and fakes

Because modern knappers legally quarry Glass Buttes, a huge share of 'Great Basin' obsidian points on the market is modern; hydration analysis or provenance is the only reliable test. Sandblasting and sand-tumbling are used to dull new points.

Cite this article

Stratum Strata. "Obsidian (Glass Buttes)" (Material). Stratum Strata pack 2026.09, as of 2026-09-21. https://stratum.black/strata/materials/obsidian-glass-buttes. Accessed 2026-09-21.

@misc{stratum-obsidian-glass-buttes,
  title        = {Obsidian (Glass Buttes)},
  author       = {{Stratum Strata}},
  howpublished = {\url{https://stratum.black/strata/materials/obsidian-glass-buttes}},
  year         = {2026},
  note         = {Material article, Stratum Strata pack 2026.09, as of 2026-09-21; sources: stratum, commons. Accessed 2026-09-21.}
}

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