The two ancient obsidian flakes recovered from a now submerged archaeological site beneath Lake Huron represent the oldest and farthest east confirmed occurrence of western obsidian in the continental United States.

A scuba diver near a submerged hunting structure at the bottom of Lake Huron.

The two ancient obsidian artifacts were recovered from a sample of sediment that was hand excavated at a depth of 32 m (105 feet) in an area between two submerged hunting structures at the bottom of Lake Huron.

Photomicrographs of the two obsidian flakes from Lake Huron.

Central Oregon obsidian from a submerged early Holocene archaeological site beneath Lake Huron