Texture (grain size, shape, sorting): Mostly sand (1/16 - 2mm grains). Composition (detrital, biochemical, chemical): Detrital sediment grains; derived from the mechanical and chemical weathering of continental rocks, which are comprised mostly of…

Common Forms/Occurrences: Found near hot springs and volcanic regions Useful Identification Test: Identifiable odour when mixed with water (resembles rotton eggs) Chemical formula: S Crystal System: Transparent to translucent crystals or earthy…

Mineralogical Composition: Visible sparkling crystals of platy minerals, bladed crystals, or prismatic crystals; breaks along scaly foliated surfaces Texture (grain size, shape, sorting): Medium to coarse grained; Folitated Metamorphic grade:…

Common Forms/Occurrences: In veins associated with other sulfide minerals Useful Identification Test: Decomposed by H2SO4 and by dilute HNO3 Chemical formula: PbS Crystal System: Forms cubes and octahedrons Colour: Silvery gray Streak: Gray to dark…

Texture (grain size, shape, sorting): Black, layered, brittle rock Composition (detrital, biochemical, chemical): Biochemical sediment grains; plant fragments and/or charcoal Other distinctive properties: May be sooty or bright Common depositional…

Mineralogical Composition: Felsic, Intermediat, and Mafic; Muscovite, Quartz, Potassium Feldspar, Plagioclase Feldspar, Amphibole, Biotite; Olivine, Pyroxene Texture (extrusive/intrusive): Extrusive; Glassy Other distinctive properties: Dark green…

Common Forms/Occurrences: Found in hydrothermal deposits Useful Identification Test: Insoluble in HCl; When powdered soluble in strong HNO3 Chemical formula: FeS2 Crystal System: Cubes and octahedrons Colour: Brass yellow Streak: Dark gray Lustre:…

Mineralogical Composition: Black glossy rock that breaks along uneven or conchoidal fractures Texture (grain size, shape, sorting): Fine grained; Nonfoliated Metamorphic grade: High Precursor rock: Peat, Lignite, Bituminous coal Commercial…

Common Forms/Occurrences: Secondary mineral formed by alteration of magnesium silicates (ie. Olivine and pyroxene) Useful Identification Test: Very soft to the touch, soapy feel Chemical formula: Mg3Si4O10(OH)2 Crystal System: Cryptocrystalline…

Mineralogical Composition: Visible crystals of two or more minerals in alternating light and dark foliated layers Texture (grain size, shape, sorting): Medium to coarse grained; Folitated Metamorphic grade: Intermediate Precursor rock: Mudstone,…

Texture (grain size, shape, sorting): No visible grains; dark, very fine-grained rock, usually breaks with a conchoidal fracture Composition (detrital, biochemical, chemical): Biochemical sediment grains; shells and shell/coral fragments, and/or…

Common Forms/Occurrences: Found in alabaster, satin spar, and selenite Useful Identification Test: Soft; Shows better cleavage than talc Chemical formula: CaSO4 ? 2H20 Crystal System: Tabular crystals, prisms, blades, or needles Colour: Colourless,…

Texture (grain size, shape, sorting): Rounded gravel, poorly sorted grains larger than 2mm Composition (detrital, biochemical, chemical): Detrital sediment grains; Rock fragments and/or quartz grains and/or feldspar grains and/or clay minerals Other…

Common Forms/Occurrences: Common constituent of Precambrian iron-formations Useful Identification Test: Attracted to a magnet and can be magnetized Chemical formula: Fe3O4 Crystal System: Octahedrons Colour: Silvery gray to black Streak: Dark gray…

Common Forms/Occurrences: Associated with galena and in hydrothermal veins in igneous rocks and contact metamorphic deposits Useful Identification Test: Soluble in HCl with evolution of H2S Chemical formula: ZnS Crystal System: Misshapen…

Common Forms/Occurrences: Two groups classified as Pyralspite and Ugrandite Useful Identification Test: Soluble with difficulty in HF Chemical formula: complex silicate Crystal System: Dodecahedrons Colour: Usually red, black, or brown; sometimes…

Mineralogical Composition: Intermediate; Quartz, Potassium Feldspar, Plagioclase Feldspar, Pyroxene, Amphibole, Biotite Texture (extrusive/intrusive): Intrusive; Phaneritic: coarse-grained Other distinctive properties: Dark gray; sold commercially…

Mineralogical Composition: Felsic and Intermediate; Muscovite, Quartz, Potassium Feldspar, Plagioclase Feldspar, Pyroxene, Amphibole, Biotite Texture (extrusive/intrusive): Extrusive; Vesicular Other distinctive properties: White, yellowish, gray to…

Common Forms/Occurrences: Igneous and metamorphic rocks Useful Identification Test: Lack of colour, low relief, and albite twinning Chemical formula: NaAlSi3O8 to CaAl2Si2O8 Crystal System: Striated tabular crystals or blades Colour: Colourless,…

Mineralogical Composition: Mostly visible crystals of amphibole Texture (grain size, shape, sorting): Medium to coarse grained; Folitated or Nonfoliated Metamorphic grade: High Precursor rock: Basalt, Gabbro, or Ultramafic igneous rocks Commercial…

Common Forms/Occurrences: Found in granites and pegmatites Useful Identification Test: Can be split into thin flexible transparent sheets Chemical formula: KAl2(Al,Si3O10)(OH,F)2 Crystal System: Short opaque prisms Colour: Colourless, yellow, brown…

Mineralogical Composition: Dull luster; breaks into hard flat sheets along the slaty cleavage Texture (grain size, shape, sorting): Fine grained; Foliated Metamorphic grade: Low Precursor rock: Mudstone or shale Commercial applications: Roofing…

Common Forms/Occurrences: Mainly of sedimentary origin Useful Identification Test: May be attracted to a magnet after heating Chemical formula: Fe2O3 Crystal System: Thin tabular crystals or massive Colour: Silvery gray, black, or brick red Streak:…

Common Forms/Occurrences: Always of secondary origin resulting from the alteration of other ores or minerals containing iron Useful Identification Test: Hard or soft; Chemical formula: Fe2O3 ? nH2O Crystal System: Amorphous masses Colour: Yellow…

Common Forms/Occurrences: Occurs in large masses in veins and pegmatites Useful Identification Test: Insoluble in acids except HF; soluble in molten Na2CO3 Chemical formula: SiO2 Crystal System: Hexagonal prism and pyramids Colour: Usually…