BOULDER — Patrick Mahaffy was just getting a little routine landscaping done outside his Boulder home -- the work crew was shaping a small drainage ditch -- when a shovel hit stone.
The "chink" of the impact sounded odd, so the crew poked around, and just 18 inches beneath the soil surface they made an extraordinary find: 83 stone tools left in a cache 13,000 years ago by people who used the sharpened rocks to butcher ice-age camels and horses.
"This is the only time in my career that this is ever going to happen to me," said Douglas Bamforth, an archaeologist at the University of Colorado who researched the find after Mahaffy contacted the university. "To have something like this appear -- to have it be what it turns out to be -- it's quite spectacular."
Bamforth conducted a biochemical analysis of the tools and found protein residue from camels, horses, sheep and bear that roamed North America at the end of the last ice age. The tools found on Mahaffy's property is only one of two Clovis-era caches -- the other is from Washington State -- that have been analyzed for protein residue.