talc (talk)

[Formerly also talk, talck = D. G. Dan. Sw. talk; is not infrequently formed by the alteration of other minerals, particularly the magnesian silicates of the pyroxene group; thus, ren elaerite is talc pseudomorphous after pyroxene, and a fibrous form of talc (sometimes called agalite ), pseudomorph after enstatite, is found at Edwards, New York, and when finely ground is used in giving a glo to paper. Talc is also used as a lubricator, and steatite or soapstone for hearthstones, etc. All this promontory seems to have been the kingdom of Carpasia. I observed in this part a great quantity of tale in the hills. Pococke , Description of the East, II. i. 218. Oil of talct. See oil. talc (talk), v. t. [ A gla plate is first cleaned, talced , and collodion i zed. The Engineer , LXVI. 334. talc a gum. See gum arabic, under gum2. Talchir group. [So called from Talchir, one of the tributary states of Ori a, in India.] In geol., the lowest division of the Gondwana se ries, a group of rocks of importance in India, consisting chiefly of shales and sandstones, which are almost entirely destitute of fo ils, although having a maximum thickne of 800 feet, and extending over a wide area. The Gondwana system is believed by the geologists of the Indian Survey to range in geological age from the Permian to the Upper Jura ic.