Each bid is for ONE thought provoking piece of Precambrian rock. This material is from the Belt Supergroup and preserves approximately 20 years of sedimentation in an ancient lake 1.4 billion years ago. You can see the alternating light and dark bands representing summer and winter seasons and they can be easily counted to see just how many years are captured in this geological snap shot. Amazing stuff and each slice comes housed in a high quality display case with dual labels. Just incredible to think about how evidence of a long vanished lake and its local climate is preserved in these bands - thick bands generally suggest wetter periods where more sediment was washed off the land into the lake. You can see from the thickness of the band which were the wettest years!
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