In turn, the end of certain stone tool industries of the period coincides with the onset of a new, drier climate. (sciencedaily.com)
If possible, a sample stone should be turned in for analysis to determine for certain the stone type. (marvistavet.com)
After reading Russian filings to UNCLOS, Margaret Hayes, of the Office of Ocean and Polar Affairs at the U.S. Department of State, indicated that «the U.S. view of Arctic geology is changing,» specifically about the meaning of certain stones found on the seafloor.16 (sciencediplomacy.org)