Home > Sterling Hill – May 29 > MS0945 Pyrochroite

Pyrochroite - Sold

Pyrochroite is a manganese hydroxide mineral related to brucite. Igelström (1864) named the mineral using the ancient Greek for fire and color, since the mineral changes color on heating. This specimen was originally labeled feitknechtite, which may be present. However, the bulk of this specimen is cleavable massive pyrochroite. The feitknechtite may occur in the sooty alteration, but it would be require careful micropowder X-ray diffraction to establish its presence. The pyrochroite crystal grains to 1.6 cm across show some pinacoidal faces, which appear to be true crystal faces and not cleavages. Quite a good example.

This specimen comes from the Bob Trimingham collection, a collector from Livermore, California. His detailed collection card indicates purchase from T.L. Baskin & Sons in 1967.