Fiorite

Fiorite
General
Category	Mineraloid
Formula (repeating unit)	SiO2·nH2O
Identification
Luster	pearly

Fiorite is a hydrated silica rock, a form of opal, found in cavities in volcanic tuff. It is a globular, botryoidal or stalactic concretionary form of opal. It has a pearly lustre and forms botryoidal masses. It was named after Santa Fiora, in Italy. It is used as a gemstone.

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