Talc

Talc (derived from the Persian tālk (تالک ), Arabic talk (تلك)) is a mineral composed of hydrated magnesium silicate with the chemical formula H2Mg3(SiO3)4 or Mg3Si4O10(OH)2. In loose form, it is the widely used substance known as talcum powder. It occurs as foliated to fibrous masses, and in an exceptionally rare crystal form. It has a perfect basal cleavage, and the folia are non-elastic, although slightly flexible. It is the softest known mineral and listed as 1 on the Mohs hardness scale. It can be easily scratched by a fingernail. It is also sectile (can be cut with a knife). It has a specific gravity of 2.5–2.8, a clear or dusty luster, and is translucent to opaque. Talc is not soluble in water, but it is slightly soluble in dilute mineral acids. Its colour ranges from white to grey or green and it has a distinctly greasy feel. Its streak is white.

Soapstone is a metamorphic rock composed predominantly of talc.

Read more about Talc:  Formation, Occurrence, Uses, Safety

Other articles related to "talc":

Talc - Safety
... Talc powder is a household item, sold globally for use in personal hygiene and cosmetics and used by many millions every year ... Toxicology Program report, which found that cosmetic grade talc containing no asbestos-like fibres was correlated with tumour formation in rats (animal testing) forced to inhale talc for 6 hours a day, five days a ... A 1971 paper found particles of talc embedded in 75% of the ovarian tumors studied ...
Transport And Logistics Centre
... The Transport and Logistics Centre (TALC) is a national policy and practice research centre based in Sydney, Australia ... and skills development - especially mentoring, innovation and knowledge sharing.From 2007 TALC became a not-for-profit company limited by guarantee with the same mandate as before, but with a ... TALC is currently working with companies and unions and in T L industry, and with the Commonwealth Department of Infrastructure and Transport ...
Sterile Talc Powder
... Sterile talc powder is a mineral, usually used in a powdered form ... In cancer treatment, sterile talc powder is used to prevent pleural effusions (an abnormal collection of fluid in the space between the lungs and the chest wall) ... Sterile talc powder is inserted into the space, causing it to close up, so fluid cannot collect there ...
Transportation And Land Use Coalition
... The Transportation and Land Use Coalition (TALC) is a non-profit organization which serves as a partnership of over 100 organizations in the San Francisco Bay Area focused on smart ... TALC was founded in 1997, and is based in Oakland, California ... A year after its founding, TALC's involvement in public-transportation advocacy was cited as part of a shift toward public support for increasing funding for buses, trains, and bike paths ...
Asbestos Fibers - Contamination of Other Products - Asbestos and Talc
... Talc is sometimes contaminated with asbestos ... in three out of eight bigger brands of children's crayons that are made partly from talc Crayola, Prang, and RoseArt. 2000, Binney Smith, the maker of Crayola, and the other makers agreed to stop using talc in their products, and changed their product formulations in the United States ...