A black coloured streak plate made form porcelain, they are used by field geologists and students as a means of performing streak tests on minerals. This test simply involves one, scratching the surface of the tile with a particular rock or mineral, the coloured streak left behind then assists the user in determining the mineral, or minerals within a rock sample. (See below a list of some common minerals and their streak colours). The tiles are made from porcelain, a strong, tough material and also has a matt finish and a very slight, fine textured surface. They are black in colour, thus making them more suitable for minerals which leave a pale or light coloured streak, which owuld not show up or be difficult to obsere on a white streak plate. Each plate measures 45 x 45 mm each and come supplied single with discounts available on quantities. Common minerals and their streaks Baryte – White Calcite – White Chalcopyrite – Dark Green/Black Galena – Grey Garnet – Lead Grey Gypsum – White Hematite – Dull Red Pyrite – Green/Black
