Colorado Stromatolite

Description

Stromatolites are formed by a blue-green bacteria that produce the lime that ultimately makes limestone. Over time these form algal mats, which in turn became the Earth's oldest fossils. Interestingly, these mats are still being formed in Australia. In northwestern Colorado, about 70 miles from the Dinosaur National Monument, stromatolites can be found in washes that also contain flint. That is where this piece was found.
I noticed some cracking in the piece before I started cutting slabs and used some penetrating glue to help hold it together. While it worked to a certain extent, you can see that a portion of the outer crust still fell off. This slab is approximately 5.25 x 2.5 x 0.5 inches and weighs 6.55 ounces.
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