Stone	Formula	Group	Other Information
	Malachite	Cu2CO3(OH)2	Carbonates	green-source of Cu-forms by reactions of Cu minerals
	Mangano Calcite	CaCO3	Carbonates	contains some manganese which gives it a pink colour
	Marble	variable	Metamorphic	variable colour-formed by alteration of sed. rocks
	Marcasite	FeS2	Sulphides	yellow-similar to pyrite
	Mica	-	Silicates	variable colour-light mica contains Al-dark contains Fe
	Mica Schist	-	Metamorphic	variable colour-contains muscovite,biotite
	Mimetite	Pb5(AsO4)3Cl	Arsenates	forms in lead deposits-rare
	Mookaite	SiO2	Silicates	form of jasper
	Moonstone	KAlSi3O8	Silicates	colourless-orphoclase feldspar
	Morganite	Be3Al2Si6O18	Silicates	pink-variety of beryl
	Moss Agate	SiO2	Silicates	variable colour-usually white-contains impurities
	Muscovite	KAl2(Si3Al)O10 (OH,F)2	Silicates	silver, grey or colourless-form of mica
	Nacre	variable	Organic	colourless-aka mother of pearl-formed from shells
	Nephrite	Ca2(Mg,Fe) 5Si8O22(OH)2	Silicates	green-source of jade-colour due to Fe
	Obsidian	-	Extru Igneous	black/grey-forms when lava solidifies quickly
	Olivene	(Mg,Fe)2SiO4	Silicates	green to yellow-aka peridot
	Onyx	SiO2	Oxides	variety of chalcedony-brown/white-similar to agate
	Oolitic Limestone	-	Sedimentary	white-forms in shallow waters-mostly CaCO3
	Opal	SiO2nH2O	Oxides	variable colour-variety of quartz-H2O attached to it
	Opalite	SiO2nH2O	Oxides	variety of quartz
	Orphoclase	KAlSi3O8	Silicates	colourless-an alkali feldspar
	Peridot	(Mg,Fe)2Si4	Silicates	green-an olivine-colour due to Fe
	Piemonite	Ca2(Mn,Fe)Al2 Si3O12OH	Silicates	member of epidote group
	Pink Chalcedony	SiO2	Oxides	pink-due to presence of Fe oxide impurities
	Pink Tourmaline	Na(Mg,Fe,Li,Mn, Al)3Al6(BO3)3 Si6O18(OH,F)4	Silcates	a complex boro silicate
	Porphyry	-	Igneous	variable colour-any ign. rock with distinct crystals
	Prehnite	Ca2Al2Si 3O10(OH)2	Silicates	colourless-any colour due to impurities
	Pumice	-	Igneous	white-lava cooled too quickly for crystallization
	Pyrite	FeS2	Sulphides	yellow-AKA fools gold (Fe sulphide)
	Pyrolusite	MnO2	Oxides	black/grey-source of Mn-found at sea bottom
	Pyromorphite	Pb5(PO4)3Cl	Phosphates	usually green-a phosphate of lead
	Pyrrhotine	FeS	Sulphides	yellow/red-an Fe sulphide mineral

Chemical Symbols