|  This
ranks as one of the prettiest pieces of stromatolite
I've ever seen. Normally, stromatolite is polished to a glass-like finish to bring
out the multicolored banding produced as the colonies organisms grew, died, multiplied
and grew another layer. A very limited part of this Ordovician Cryptozoon stromatolite
formation underwent partial recystalization. The result was numerous small crystal
points that grew with a strawberry-like color more beautiful than the prettiest
smokey quartz I have seen. Thus, we have a fossil of the oldest type of organism
in the fossil record that has been transformed by nature into a most aesthetic
rendering.
Interestingly,
coming from a Lower Ordovician formation, this stromatolite was formed just prior
to the second major (and final) decline of the stromatolite
building organisms. The silica-based quartz is the result of mineralization from
the adjacent bentonite deposites in which the stromatolite is buried. The bentonite
of this formation, in turn, is believed the outcome of a meteorite strike in close
proximity to the stromatolite colony that, given no stromatolite occurs in upper
layers, extinguished the colony that formed this fossil. |
