Stone	Formula	Group	Other Information
	Halite	NaCl	Halides	colourless-aka rock salt-found in evaporite deposits
	Heliotrope	SiO2	Oxides	green with red spots-aka bloodstone-red due to Fe
	Hematite	Fe2O3	Oxides	red to black-source of Fe-becomes red when exposed to oxygen
	Hemimorphite	Zn4Si2O7 (OH)2H2O	Silicates	Variable colour-forms when zinc veins are altered by oxidation
	Hessonite	Ca3Al2(SiO4)3	Silicates	yellow/orange-colour due to Fe-member of garnet group
	Hornblende		Silicates	green to black-complex chemical composition-an amphibole
	Howlite	Ca2B5SiO9 (OH)5	Silicates	white-often stained to look like turquoise
	Iceland Spar	CaCO3	Carbonates	colourless-form of calcite-first extracted in Iceland
	Iolite	(Mg,Fe)2Al4 Si5O18	Silicates	violet-aka cordierite
	Iris Quartz	SiO2	Oxides	colourless-diffracts light due to crystal structure
	Ironstone		Sedimentary	brown/yellow-Fe rich-often cemented by calcite and dolomite
	Jadeite	NaAlSi2O6	Silicates	colourless-usually green due to Cr impurities-source of jade
	Jasper	SiO2	Oxides	variable colour (depends to nearby minerals)
	Jet		Organic	black-formed from wood fallen into stagnant water-C rich
	Kainite	KClMgSO4 3H2O	Sulphates	colourless-produced by evaporated salt water
	Kunzite	LiAlSi2O6	Silicates	lilac to pink-form of spodumene-colour due to Mn
	Labradorite	(Na,Ca)Al1-2Si3-2O8	Silicates	colourless-a plagioclase feldspar
	Lace Agate	SiO2	Oxides	blue/white-form of chalcedony
	Lapis Lazuli	(NA,Ca)8 (Al,Si)12 O24(S,SO4)	Silicates	blue-found when limestones make come with calcite & pyrite
	Larimar	NaCa2Si3O8 (OH)	Carbonates	A pectolite-only found in the Caribbean
	Lepidolite	K(LiAl)3(SiAl)4 O10(FOh)2	Silicates	source of lithium-belongs to the mica group
	Limonite	FeO(OH)nH2O	Oxides	yellow to brown-a group of Fe oxides and hydroxides
	Magnesite	MgCO3	Carbonates	white/grey-forms in hydrothermal veins
	Magnetite	Fe3O4	Oxides	black-source of Fe

Chemical Symbols