L-990 (Briar Creek Chert): Provenience includes gravel deposits. Not a collection from archaeological context. Collection includes raw material, outer surface, modern flint-knappers' work, and ...
Jaspers and cherts are the rocks most often confused with Lake Superior agates Lakers formed when mineral-infused solutions seeped into the gas bubbles of volcanic rocks Lake Superior agates are ...
Some results have been hidden because they may be inaccessible to you
Show inaccessible results