Browse Items (264 total)

Formula NaCl Structure Non-silicate Crystal System Crystal system: cubic Physical Properties Colour in hand specimen: colourless or white when pure, more typically orange or red due to inclusions of iron compounds, and may also be grey,…

Formula CaF2 Structure Non-silicate Crystal System Crystal system: cubic Physical Properties Colour in hand specimen: extremely variable: colourless, white, yellow, green, blue and purple most commonCleavage: perfect octahedral, up to…

Formula Ca5(PO4)3(OH,F,Cl) Structure Non-silicate Crystal System Crystal system: hexagonal (-) Physical Properties Colour in hand specimen: green, white, yellow, blue brown etc.Hardness: 5 Optical Properties Colour in plane polarised…

Formula CaMg(CO3)2 Structure Non-silicate Crystal System Crystal system: trigonal (-) Physical Properties Colour in hand specimen: white, often tinged with yellow or brown Cleavage: rhombohedral Hardness: 3.5-4  Optical…

Formula CaCO3 Structure Non-silicate Crystal System Crystal system: trigonal (-) Physical Properties Colour in hand specimen: whiteCleavage: rhombohedralHardness: 3 Optical Properties Colour in plane polarised…

Formula CaSO4 Structure Non-silicate Crystal System Crystal system: orthorhombic (+) Physical Properties Colour in hand specimen: white or colourless when pure Cleavage: two at 90° Hardness: 3-3.5 Optical Properties Colour in plane…

Formula CaSO4∙2H20 Structure Non-silicate Crystal System Crystal system: monoclinic (+) Physical Properties Colour in hand specimen: usually white or colourlessCleavage: rhombohedral, one perfect, two distinctHardness: 2 Mineral…

Formula PbS Structure Non-silicate Crystal System Crystal system: cubic Physical Properties Colour in hand specimen: lead greyStreak: lead greyLustre: metallicCleavage: one, perfectHardness: 2.5 Optical Properties Colour in plane…

Formula FeS2 Structure Non-silicate Crystal System Crystal system: cubic Physical Properties Colour in hand specimen: pale brassy yellow; black when fine-grainedStreak: greenish or brownishLustre: metallicCleavage: not…

Formula Fe3O4 Structure Non-silicate Crystal System Crystal system: cubic Physical Properties Colour in hand specimen: blackStreak: blackCleavage: noneHardness: 7.5-8 Optical Properties Colour in plane polarised light: almost…