It's a match of obscurity vs ubiquity as Vivianite faces off against Spinel.

The popular Lady of Darkness Vivianite returns from peat bogs and old bones to do battle once again. This mineral starts colourless, then oxidizes to green, blue, and eventually black. It's soft enough to cut with a knife, and flexible enough to psuedomorph after wood and other fossils.

Newcomer Spinel is so iconic that it lends its name to an entire mineral classification group. Spinel the mineral is a gemstone, found everywhere from the upper mantle to inclusions in meteorites older than the Earth itself.

Both minerals are worthy of praise, but only one can move on to Round 2!

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