Talc also is widely distributed in the state; the most extensive beds are in the south-western counties, Swain and Cherokee.
Mica, talc, chlorite, haematite), or in long blades or fibres (anthophyllite, tremolite, actinolite, tourmaline), and, when these have a well marked parallel arrangement in definite bands or folia, the rock will break far more easily along the bands than across them.
Serpentine into talc-schist, dolerite into hornblende-schist) by the same agencies.
Talc-schists are of the same category.
The value of the clay products, lime and talc, decreased from $245,378 in 1907 to $112,815 in 1908.
Near Talcville, in St Lawrence county, is a large deposit of fibrous talc. In 1908 the total value of the state's talc product was $ 6 97,39 0, almost one-half the total for the entire country.
Glass and other sands and gravel ($13,270,032), lime ($11,091,186), phosphate rock ($10,653,558), salt ($7,553,632), natural mineral waters ($7,287,269), sulphur ($6,668,215, almost wholly from Louisiana), slate ($6,316,8 I7), gypsum ($4,138,560), clay ($2,599,986), asphalt ($1,888,881), talc and soapstone ($1,401,222), borax ($975,000, all from California), and pyrite ($857,113) were the next most important products in 1908.
Grindstones, building-stone, talc, gypsum, marble and phosphates are also produced.
Magnesium is found widely distributed in nature, chiefly in the forms of silicate, carbonate and chloride, and occurring in the minerals olivine, hornblende, talc, asbestos, meerschaum, augite, dolomite, magnesite, carnallite, kieserite and kainite.
It is the hardest known substance (though tantalum, or an alloy of tantalum now competes with it) and is chosen as io in the mineralogist's scale of hardness; but the difference in hardness between diamond (io) and corundum (9) is really greater than that between corundum (9) and talc (1); there is a difference in the hardness of the different faces; the Borneo stones are also said to be harder than those of Australia, and the Australian harder than the African, but this is by no means certain.
From these rocks in the Ottawa valley are quarried or mined granite, marble, magnificent blue sodalite, felspar, talc, actinolite, mica, apatite, graphite and corundum; the latter mineral, which occurs on a larger scale here than elsewhere, is rapidly replacing emery as an abrasive.
The oldest rocks exposed are gneiss, talc-schist and serpentine, with intrusive masses of gabbro and diabase.
Crystal is a noted product of Korea, and talc of good quality is also present.
The product of talc and soapstone in 1908 was 19,616 short tons, valued at $458,252.
The black variety of cochineal is sometimes sold for silver cochineal by shaking it with powdered talc or heavy-spar; but these adulterations can be readily detected by means of a lens.
The primary rocks which appear at Mitushev Kamen are overlaid with thick beds of quartzites and clayslates containing sulphide of iron, with subordinate layers of talc or mica slate, and thinner beds of fossiliferous limestone, Silurian or Devonian.
TALC, a mineral which in its compact forms is known as steatite, or soapstone.