Wood's Chrome Mine (Wood's Mine), Texas, Little Britain Township, State Line Chromite District, Lancaster Co., Pennsylvania, USA

Mg(OH)₂

Crystal System: trigonal
Colour: white, light greenish, grayish, bluish; honey-yellow, brown or red-brown
Lustre: vitreous, waxy, pearly
Habitus: tabular, but sometimes foliated
Hardness: 2½ - 3
Fracture: fibrous or micaceous
Cleavage: perfect on {0001}
Density: 2.368 g/cm³
Origin and geological occurrence: brucite is found in low-temperature hydrothermal veins, in metamorphic limestones and chlorite schists; formed during serpentinization of dunites. It is also a common alteration of periclase in marble. 

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Smorf link

Samples:

4.17 Brucite Vein of light-blue micaceous crystals in marble. Veneto, Italy. #oxides