Embreyite

embreyite

crocoite

vauquelinite

fornacite

Images

Formula: Pb5(CrO4)2(PO4)2.H2O
Hydrated chromate
Crystal System: Monoclinc
Specific gravity: 6.45 measured, 6.564 calculated
Hardness: 3½
Streak: Yellow
Colour: Dull orange
Environments

Hydrothermal environments

Localities

At the Callenberg North open cut No. 1, Callenberg, Zwickau District, Saxony, Germany, embreyite is associated with crocoite, vauquelinite, fornacite, pyromorphite, mimetite and cerussite (HOM).
Embreyite from Callenberg - Image

At the type locality, the Berezovsk deposit, Beryozovsky, Sverdlovsk Oblast, Russia, embreyite occurs on those specimens rich in other chromates, particularly crocoite and phoenicochroite. It is later than crocoite, which it may implant and replace, and was not observed in direct contact with the still earlier phoenicochroite. Cerussite is later than, and may replace embreyite. Vauquelinite was also observed replacing embreyite directly. Embreyite also occurs as thick botryoidal crusts.
The chromates at Berezov usually occurred in gold-bearing quartz veins.
Pure embreyite is dull orange in colour, the streak is primrose yellow, the lustre may be dull to sparkling and resinous, and crystalline material is transparent or transluscent in mass. (MM 38.790-793).
Other associated minerals observed on museum samples from the oxidised zone of the gold-bearing quartz veins include cassedanneite (HOM).
Embreyite from the Berezovsk deposit - Image

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