Mineralpedia Details for Gilalite
Named for the type locality in the Christmas mine in Gila County, Arizona in the United States. Gilalite is a rare mineral that can only be found in Arizona and Nevada in the USA, in Greece at Laurion, and in Brazil. At its type locality, Gilalite is “a retrograde metamorphic or megogene mineral formed at the expense of a prograde calc-silicate and sulfide assemblage, in tactites commonly incrusting fractures, [and] also filling cracks or interstices in diopside grains.”
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/gilalite.pdf
Gilalite from Christmas mine, Gila Co., Arizona, United States
Light green spheroidal crystals to about 0.75mm.
Dozens of pastel green, smooth bead-like crystals to about 0.75mm.
Green spherical crystals to 0.3mm in bunches with Stringhamite.