What is talc solubility in water


Author: Torsten Purle (steine-und-minerale.de) | Last update: April 13th, 2021

Talc - properties, origin and use

english: talc | French: talc

Talc - a very soft mineral

The name Talk originally comes from the Arabic-Persian language area and will with soft translated, referring to the low hardness of the mineral. Alternatively, talc is also known as soapstone and refers to the mineral surface that feels oily or soapy.

Properties of talc

Talc is with the chemical composition Mg3Si4O10(OH)2 a mineral of the class of silicates.

The color of talc is different and varies depending on the elementary admixtures.
Pure talc is white; as a result of admixtures, the mineral appears greenish, grayish and brownish to reddish or yellowish.
The line color is always white.

Talc crystallizes in the monoclinic crystal system, the crystals formed are thin tabular. The aggregates appear as compact masses or are scaly, kidney-shaped and leafy.

The shine of the magnesium silicate hydrate is greasy to mother-of-pearl with transparent to translucent transparency. The fracture of talc is uneven, the cleavage is very perfect.

With a Mohs hardness of 1 on the 10-point scale of the hardness of minerals according to the mineralogist Friedrich Mohs (1773 to 1839), talc is the mineral with the lowest known hardness. However, if talc is exposed to high temperatures in the melting furnace, the mineral gains resistance and sometimes reaches a Mohs hardness of up to 6. The density is 2.58 to 2.83 g / cm3.

Formation and dissemination of talk

Talc is created when basic rocks and minerals are transformed by hydrothermal processes. For this reason, talc is found in many passages or as a filler material between slates.

Talc deposits are often accompanied by dolomite (rock), quartz, serpentine, dolomite (mineral), chlorite, calcite, magnetite, magnesite and actinolite.

Talks are found in Sula / Norway, among others; Falun / Sweden; Urals / Russia; Fichtelgebirge, Kyffhäusergebirge / Germany; France; St. Gotthard, Zermatt / Switzerland; Silesia / Poland; Slovakia, Czech Republic; Florence / Italy; Hungary; Japan; Transvaal / South Africa; Brazil and USA.

Use and meaning of talk

Talc is a versatile mineral.
In cosmetics and pharmaceutical production, powdered talc is used as the basis for powders and ointments as well as for the manufacture of soaps, recognizable in the ingredients under the Latin name talc.
Talc is also used as an additive for the production of paper and as a white pigment for paints and varnishes.
In the past, massive pieces of talc were used as starting material for stonemasons who made vessels or sculptures from talc.
In addition, cube-shaped talc is sold as a whiskey stone, which is used as an alternative to ice for cooling whiskey without the drink watering down or changing its taste.
As already mentioned earlier in the text, talk becomes harder when it burns. That is why the mineral is often used in the construction industry, and burnt talc is also fireproof.

Evidence of talk

Talc is not soluble in water or acids. Due to its low hardness, talc can easily be scratched with the fingernail and feels soapy.

See also:
⇒ Everyday things - baby powder
⇒ Stone paper - writing on stone
⇒ Mineral cactus soil

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⇒ Bauer, J .; Tvrz, F. (1993): The Cosmos Mineral Guide. Minerals rocks precious stones. An identification book with 576 color photos. Gondrom Verlag GmbH Bindlach
⇒ Korbel, P .; Novak, M. and W. Horwath (2002): Mineralien Enzyklopädie, Dörfler Verlag
⇒ Medenbach, O .; Sussieck-Fornefeld, C .; Steinbach, G. (1996): Steinbach's natural guide minerals. 223 species descriptions, 362 color photos, 250 drawings and 30 pages of identification tables. Mosaik Verlag Munich
⇒ Schumann, W. (1992): Precious and precious stones: all precious and precious stones in the world; 1500 unique pieces. BLV determination book, BLV Verlagsgesellschaft mbH Munich
⇒ Schumann, W. (1991): Minerals rocks - characteristics, occurrence and use. FSVO nature guide. BLV Verlagsgesellschaft mbH Munich
- www.mindat.org - talc