A mammoth carving, designed out of a horse's shoulder blade, was found in waters covering the ancient

Bering Strait and land bridge. A 0.500-gram piece of this bone was observed to undergo 1,187 carbon-14

decays in a 1-hour period. A 0.500-gram piece of bone from a modern source underwent 7,251 carbon-14

decays in the same period. Approximately how old is this bone carving?