The talc
The talc, Magnesium Hydrate Phyllosilicate Mg3 [(OH2) /Si4O10] is a secondary genesis mineral that formed itself later than its country rock. Bagnada talc has formed at “the expenses” of the dolomitic marbles, white metamorphic rocks characterized by a sugar-like aspect and for this reason called saccharoid dolomite. They are similar to the sediments of shallow and quiet seas, going back to medium-Triassic Age (about 230 million years ago), transformed by the metamorphism.
The veins that are extracted and set along fractures north-eastward/south-westward with a variable power from 10 to 20 mt. Talc, which is white and schistose, is oily when you touch it and has a hardness of 1 in the Mohs scale.
Talc nowadays
Valmalenco is still involved in the grey talc or steatite extraction activity, with just one active mine (Brüsada – Ponticelli).
The two mineralizations, the Bagnada one and the Brusada one, differ from their origin, aspect and for their
country rock. The talc coming from these latest extractions is not as pure as the Bagnada white one and is employed in different fields. Here below, you can find some of them.
Plastics: Talc is a stiffening in plastics. It is widely used in the car sector (dashboards, bumpers, interior finish), in the house tools and packing manufacturing.
Paper industry: it is employed as a dispersing agent of the cellulose organic impurities and to take away ink from recycled papers. It improves the glossy paper smoothness and printability.
Paints and varnishes: talc helps to obtain a uniform drying, improves opacity and increases the cracking and corrosion endurance.
Pottery industry: it lowers the melting point and improves vitrification properties. By lowering temperatures, cooking time is reduced with a cost reduction.
Agriculture: Talc is used to prevent lumps formation: it is spread on the feed and fertilizer surface in order to give them a suitable fluidity during manufacturing and extracting from the silos phases.
Pharmaceutical industry and cosmetics: since talc is inert and safe, it is employed as an active ingredient aid in pills and other pharmaceutical preparations. In cosmetics, it is used for its opacifying qualities in foundation creams and make –up, as a thickener in liquid preparations and, of course, as a body powder.