GEOG 1120 Lecture Notes - Lecture 5: Corundum, Calcite, Birefringence
Document Summary
Lecture 5: mineral identification (part i: simple properties to id unknown minerals, colour. One mineral can have different colours and different minerals can also have the same colours. Not used for a verse specific identification: luster. The way (amount and quality) a mineral reflects light. Different types to identify the luster of minerals: E. earthy - or dull (ex: limonite: streak. Colour of the powdered form of minerals is different. Using an unglazed piece of porcelain or streak plate to grind the material in order to see the streak colour. Streak is not necessarily the colour of the mineral: hardness. Moh"s hardness scale - 1 to 10 (1 being soft and 10 being the hardest). Splitting of a mineral along planes of weakness => number of planes (ei. Angle between them (either 90 degrees or not at 90 degrees) Hints: trying to cleave a mineral, look for staircases (2d) or cubes (3d); look for shiny surfaces: fracture.
