SLE102 Study Guide - Midterm Guide: Magnetite, Conchoidal Fracture, Talc

• School: Deakin University
• Department: Science, Engineering and Built Environment
• Course: SLE102
• Professor: Nick Porch

Document Summary

Inorganic: naturally occurring, elements or compounds, process chemical and physical properties. Diagnostic physical properties used to identify minerals: crystal habit or form, mineral cleavage, colour, lure, hardness, streak, specific gravity, magnetism. Cubic - external form of a cube (e. g. galena) Rhombohedral - external form of a rhombohedron. Dodecahedral - external form of a dodecahedron (e. g. garnet) Aggregate form no definite geographic form or face. Platy - crystals occurring in thin sheets (e. g. muscovite, biotite) Granular - made up of uniform-sized grains (2-10mm) Bladed - elongate crystals flattened like a blade. Cleavage: directions of splitting / weakness within the mineral. Perfect cleavage: well-developed cleavage; smooth, even, well-defined surface. Good or poor cleavage: cleavage not to clear/developed. Many minerals have >1 cleavage plane or direction. Fracture: mi(cid:374)e(cid:396)als that do(cid:374)"t possess (cid:272)leavage, (cid:271)ut f(cid:396)a(cid:272)tu(cid:396)e i(cid:374) a(cid:374) i(cid:396)(cid:396)egula(cid:396) (cid:373)a(cid:374)(cid:374)e(cid:396). Conchoidal fracture (fractures in a concave, semicular pattern - i. e. glass) Mineral hardness: the resistance of a smooth surface of the mineral to scratching.