• To be classified as a true mineral, a substance must be a solid and have a crystalline structure. It must also be a naturally occurring, homogeneous substance with a defined chemical composition
• The International Mineralogical Association approved the following definition in 1995: A mineral is an element or chemical compound that is normally crystalline and that has been formed as a result of geological processes.
SCALE OF MHOSThe Mohs scale of mineral hardness is based on the ability of one natural sample of matter to scratch another. The samples of matter used by Mohs are all minerals. Minerals are pure substances found in nature. Rocks are made up of one or more minerals
• To be classified as a true mineral, a substance must be a solid and have a crystalline structure. It must also be a naturally occurring, homogeneous substance with a defined chemical composition.• The international mineraroligal association approved the following definition in 1995:
• "A mineral is an element or chemical compound that is normally crystalline and that has been formed as a result of geological processes." According to this definition and classification scheme, biogenic materials were excluded from the mineral kingdom: "Biogenic substances are chemical compoundsproduced entirely by biological processes without a geological component and are not regarded as minerals. However, if geological processes were involved in the genesis of the compound, then the product can be accepted as a mineral.
SCALE 1• TALC:a number of transit-related projects and ballot measures since its inception
SCALE 2• CALCIUM:is essential for living organisms, in particular in cell physiology
SCALE 3• CALCITE: is a carbonate mineral and the most stable polymorph of calcium carbonate
SCALE 4• FLOURITE:(also called fluorspar) is a halide mineral composed of calcium fluoride
SCALE 5• APATITE:Apatite is a group of phosphate minerals, usually referring to hydroxylapatite, fluorapatite, chlorapatite and bromapatite
SCALE 6• Orthoclase Feldspar:Orthoclase (endmember formula KAlSi3O8) is an important tectosilicate mineral which forms igneous rock
SCALE 7· QUARTZ:Quartz is an abundant mineral in the Earths continental crust
SCALE 8• TOPAZ:Topaz is a silicate mineral of aluminium and fluorine with the chemical formula
SCALE 9• CORUNDUM:Corundum is a crystalline form of aluminium oxide (Al2O3) with traces of iron, titanium and chromium
SCALE 10• DIAMOND:is an allotrope of carbon, where the carbon atoms are arranged in a variation of the face- centered cubic crystal structure called a diamond lattice