£7.00 ex VAT
1 kilogram of biotite mica from Pakistan, this popular black variant of mica forms in sheets with an excellent basal cleavage, often refered to as books, they are ideal for educational material or kits, supplied by weight, the mineral specimens will come in a polythene bag with an information label.
Biotite mica is a black, platy mineral which forms in sheets, it belongs to the mica group of minerals which also includes muscovite, phlogopite and lepidolite micas. It is also found in many rocks, particularly of igneous and metamorphic origin, such as mica schist, gneisses and granites. The crystal habit of mica in general is monoclinic and like other mica minerals, biotite has an excellent basal cleavage and consists of flexible sheets or lamellae, which easily flake off, with tabular to prismatic crystals. Due to this formation, when the mineral is found in multiple layers, it is often refered to as ‘books’ of mica, due to the way the sheets represent pages of a book. These particular mineral specimens are from Pakistan, the sizes supplied vary between 20 mm to 50 mm but are only 2 – 3 mm thick due to the layered form of the mineral. Supplied in a polythene bag upto a weight of 1 kilogram along with an information card.