Talc is a mineral. It is also the name given to the powder obtained after grinding the mineral: talcum powder. Massive talc in rock is called steatite. Steatite can be used for producing talc pencils or carving. Soapstone is a kind of impure talc associated with chlorite and serpentine utilised for dimensional stones cutting or for carving.

As far as the mineral is concerned, talc is a natural hydrated magnesium silicate ‎Mg3Si4O10(OH)2 the composition of which is generally closed to MgO 32/%, SiO2 63% and H20 4.75%. At the molecular scale, the mineral is formed by a stacking of elementary composite lamellas made of one layer of brucite sandwiched between two pages of silica. That is why talc is categorized into phyllosilicate subgroup (like mica), also known as sheet silicate.

Talc is a common mineral found in metamorphic geological contexts, but its economical concentrations are rare and of small sizes. It always derives from the transformation of pre-existing rocks -called mother rocks-, such as dolomitic marbles, quartzites or serpentinites. According to the mother rocks composition, the resulting talc can be found in association with other minerals like chlorite, carbonates, serpentinite or quartz. The talc marketed by Northwest derives from dolomitic marble that is why it is very pure, white and lamellar.

Considered as the softest mineral on earth the talc ranks first on Moths scale. Its colour in massive form may vary (pink, greenish, grey) but remains white for the powder. Specific gravity is 2.6. Talc is chemically neutral and inert, non-reactive to acidic and basic chemicals. Due to its molecular structure, the talc powder is lamellar, property highly appreciated in some industrial applications such as plastic filler and cosmetic. 

A DAILY LIFE MINERAL! Ground, micronized talc is converted into smooth white powder that is widely known as Talcum powder. This product having ability to absorb moisture, oils, odours, produces an astringent effect with human skin as body care agent in a large range of applications such as baby powders, cosmetic base, etc. Cosmetic is the most famous talc usages, but this is not the main application of the mineral. Other uses are far more important in term of volumes but not known from the general public. Amongst the multiple applications of the mineral let’s mention:

– Plastic industry: talc is used as a filler. The platy shape of talc particles increases the stiffness as well as heat resistance of polypropylene products especially in car industry. For instance, a modern car may contain up to 10kg of talc in its various parts.

– Ceramics industry: talc can be a raw material, but it also plays role as melting agent.

– Paint industry: talc, as a filler improves the rheology and covering power of the paint.

– Paper industry talc is used as filler, to improve mechanic properties of the sheets but also opacity and printability, brightness and whiteness of paper.

For thousands of years, steatite and soapstone have been used to make sculptures, countertops, and many other artefacts.