Talc Talc is the softest mineral, demonstrated by its position at the bottom of Mohs' Scale of Hardness with a relative hardness value of 1. It has a soapy, greasy feel. Franzelin and High Impact Photography.
Most people are familiar with the mineral known as "talc". It can be crushed into a white powder that is widely known as "talcum powder. These properties have made talcum powder an important ingredient in many baby powders, foot powders, first aid powders, and a variety of cosmetics.
A form of talc known as " soapstone " is also widely known. This soft rock is easily carved and has been used to make ornamental and practical objects for thousands of years. It has been used to make sculptures, bowls, countertops, sinks, hearths, pipe bowls, and many other objects. Although talcum powder and soapstone are two of the more visible uses of talc, they account for a very small fraction of talc consumption.
Its hidden uses are far more common. Talc's unique properties make it an important ingredient for making ceramics, paint, paper, roofing materials, plastics, rubber, insecticides, and many other products. Talc: Talc is a phyllosilicate mineral that cleaves into thin sheets. These sheets are held together only by van der Waals bonds, which allows them to easily slip past one another. This characteristic is responsible for talc's extreme softness, its greasy to soapy feel, and its value as a high-temperature lubricant.
Although the composition of talc usually stays close to this generalized formula, some substitution occurs. When large amounts of Fe substitute for Mg, the mineral is known as minnesotaite.
When large amounts of Al substitute for Mg, the mineral is known as pyrophyllite. Talc is usually green, white, gray, brown, or colorless. It is a translucent mineral with a pearly luster. It is the softest known mineral and is assigned a hardness of 1 on the Mohs Hardness scale.
Talc is a monoclinic mineral with a sheet structure similar to the micas. Talc has perfect cleavage that follows planes between the weakly bonded sheets. These sheets are held together only by van der Waals bonds, which allows them to slip past one another easily.
This characteristic is responsible for talc's extreme softness, its greasy, soapy feel, and its value as a high-temperature lubricant. In the United States, talc consumption has slowly declined since Smaller amounts of the mineral are used in the ceramics industry because of a change in firing technology.
In the paint industry, a shift from oil-based paints to latex paints has decreased the use of talc. In the cosmetics industry, many manufacturers have replaced talc with corn starch powder in many products in response to health concerns and litigation. However, the plastics industry is using more talc, as the mineral becomes a more important ingredient in automotive plastics.
There are many uses of talc, especially as an industrial mineral because of its resistance to heat, acid and electricity. Because of these resistances it can be used as counter tops, electrical switchboards, ceramics, and insecticides. It is most commonly known as the main ingredient in talcum powder. It is also an important filler in paints and rubber. Talc is used commercially because it can retain fragrance, lustre, purity, softness and whiteness. Some of the major markets for talc are ceramics, pain paper and plastics.
Ground talc is used in roofing and cosmetics. Talc can be blue, pale green, gray, pink, white, yellowish or brownish white to almost silver. Its lustre is dull to pearly or greasy. What determines these characteristics are its natural or artificial impurities.
This translates into a very soft material, which results from its layered nature. Naturally, this substance is hydrophobic dislikes water , and tends not to absorb water, therefore giving some of its favourable water-resistant characteristics. Both of these minerals are nearly identical, each being very soft. Modest production began in from shallow pits and adits, supplying steatite massive, compact, high-purity talc that was used to make ceramic insulators. The southwest Montana talc industry grew to become a significant part of the region's economy; this history is described by Perry , Olson , and Berg Exploration and development are likely to continue for the foreseeable future for several reasons: 1 mines are active in the area at present and an infrastructure for talc processing exists; 2 large changes in domestic and export talc markets are not expected in the next few years based on recent market trends Virta, ; 3 the talc of this region is especially pure and asbestos-free; and 4 except for potential ground stabilization problems and land disturbance associated with largescale open pit mining, no significant environmental impacts are associated with talc mining.
By: Bradley S.
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