talc - clinochlore soapstone - a dark green talcose mineral - teaching hand specimen

This is a complex talcose mineral, loosely called pyrophyllite at the mine in the 1940s, though it is actually clinochlore as recently confirmed by x-ray diffraction, and contains no pyrophyllite at all.

Clinochlore is the magnesium-rich end member of the chlorite group. The talcose minerals, chlorite, pyrophyllite and talc, share many of the same properties and are used interchangeably as industrial talc in the manufacture of ceramics, cosmetics, paint, paper, fiberglass, rubber and heat-resistant refractories. This is a good example of soapstone.

Clinochlore:  (Mg,Fe)₅Al₂Si₃O₁₀(OH)₈

This was mined at the Frisco Mine in the Talc City Hills, Inyo County, California. The mine was a small producer of high grade talc and was reactivated in 1942 in response to the wartime demand for talc. A large part of its early production was this dark green soapstone. It was called “chloritic rock” by the US Geological Survey in 1962.

Clinochlore is one of the most common minerals of the chlorite group. It was originally named "chlorite" in 1879 by Abraham Gottlob Werner from the Greek chloros for green. It was renamed in 1851 by William Phipps Blake, Territorial Geologist of Arizona, from the Greek klinein, to incline, referring to its inclined optic axes, and chloros, green, its typical color. It has perfect cleavage in one direction, giving clinochlore its soapy feel.

This is massive clinochlore, extracted from a vein.

Select a specimen: When more than one specimen is shown, you can select a particular specimen by telling us what is in the photo with it, a blue or black and silver pen, a black mechanical pencil or one of those plus some number of coins, or you can let us make the selection.

Shipping: in a First Class package unless combined with other items. Click > here < for shipping rates. Use back button to return to this page.