Quoting from the below article:
"In June 1936 Max Hahn and his wife Emma were on a walk beside a waterfall near to London, Texas, when they noticed a rock with wood protruding from its core. They decided to take the oddity home and later cracked it open with a hammer and a chisel. What they found within shocked the archaeological and scientific community. Embedded in the rock was what appeared to be some type of ancient man made hammer."
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