Talc is a rock that is mined from open-pit and underground deposits. Because it is a natural product, talc is always found in combination with at least one other mineral whose proportion depends on its geological origin. Chemically pure talc has never been found in nature in commercial quantities. Practically all of the talc products offered are impure. The most common host for talc ore bodies is dolomite & ultramafic rocks. Color variations range from snow-white to black, including greenish gray & various shades of green, pink and even red. Talc is an important industrial mineral. Its resistance to heat, electricity and acids make it an ideal surface for lab counter tops and electrical switchboards. It is also an important filler material for paints, rubber and insecticides. Even with all these uses, most people only know talc as the primary ingredient in talcum powder. Mineral specimens are not very common as it does not form very large crystals. However, it often replaces other minerals on an atom by atom basis and forms what are called pseudomorphs (false shape). The talc takes the form of the mineral it replaces. A specimen of what looks like milky quartz is quite a surprise when it not only has a soapy feel but can be scratched by a fingernail.