From ScienceDaily.com
QUOTE
Abundant tiny particles of diamond dust exist in sediments dating to 12,900 years ago at six North American sites, adding strong evidence for Earth's impact with a rare swarm of carbon-and-water-rich comets or carbonaceous chondrites, reports a nine-member scientific team.
Also of note........this may be proven to be the climate change factor that killed over 35 large mamal species and the Clovis native americans around 12,900 years ago and could have changed the weather globally for over a mellium!
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