Streak Plates in White, they are 40 x 40 x 5 x 0.1 (mm) and unglazed. Each Pack contains 10 Plates. Streak plates are used to identify minerals, each mineral gives off a different colour when rubbed against a plate, which is not necessarily the same colour as the rock. For example: an Amethyst which is commonly violet can be identified by a white/grey streak.
Contains a list of common minerals with hardness, colour and streak.