Hematite (beads)
Hematite (Fe₂O₃)
Mineral
Category
Mixed (Igneous, Sedimentary, Metamorphic, And Minerals)
Browse mixed (igneous, sedimentary, metamorphic, and minerals) specimens identified by the Rock Identifier community.
Schist
Mica Schist (primarily Muscovite or Biotite sheet silicates)
metamorphic
Foliated Gneiss (River-Worn Pebble)
Gneiss (High-grade Regional Metamorphic Rock)
metamorphic
Clear Quartz Cluster
Quartz (Silicon Dioxide - SiO2)
mineral
Pyrite
Iron Disulfide (FeS2)
mineral
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
mineral
Opal
Hydrated Amorphous Silica (SiO2·nH2O)
Mineral
Moonstone (Feldspar)
Orthoclase or Oligoclase (KAlSi3O8)
mineral
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 inclusions)
sedimentary
Almandine Garnet
Almandine (Fe3Al2(SiO4)3)
mineral
White Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
mineral
Quartz (likely) or a Quartzite Pebble
Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.
Mineral, specifically a detrital grain
Quartzite River Rock (with Limonite staining)
Quartzite (SiO2)
metamorphic
Orthoclase Feldspar
KAlSi3O8 (Potassium Aluminum Silicate)
Mineral
Corundum
Corundum (Aluminium oxide, Al2O3)
mineral
Bull Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
mineral
River Cobbles (Basalt, Quartzite, and Sandstone mix)
Fluvial detritus (primarily SiO2, Plagioclase, and Pyroxene mix)
Mixed: Igneous and Sedimentary
Quartz
Silicon dioxide (SiO₂)
Mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Biotite (Black Mica)
K(Mg,Fe)3AlSi3O10(OH,F)2
mineral
Milky Quartz
Silicon dioxide (SiO2)
mineral
Quartz (Milky/Common)
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Mineral
Milky Quartz with Iron Staining
Silicon Dioxide (SiO2)
mineral
Folded Schist / Gneiss (Metamorphic Rock)
Regional Metaphoric Folded Outcrop (predominantly Schist/Gneiss)
metamorphic
Specular Hematite
Hematite (Fe2O3)
mineral
Black Tourmaline (Schorl)
Schorl (Na(Fe^2+)3Al6(Si6O18)(BO3)3(OH)4)
Mineral
Milky Quartz
Quartz (Silica / Silicon Dioxide, SiO2)
mineral
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Quartz Vein in Host Rock
Quartz (SiO2) in Mafic or Sedimentary Matrix
igneous
Marble
Recrystallized Calcite (CaCO3)
metamorphic
Quartz
Quartz (SiO2 - Silicon Dioxide)
Mineral, often found as detrital grains in sedimentary rocks
Blue Sapphire
Corundum (Al2O3) with traces of Iron and Titanium
mineral
Marble
Marble (metamorphosed limestone/dolostone). Predominantly composed of Calcite (CaCO3) for marble derived from limestone, or Dolomite (CaMg(CO3)2) for marble derived from dolostone.
Metamorphic Rock
Orthoclase Feldspar (or K-Feldspar)
Orthoclase (KAlSi3O8)
Mineral
Garnet
Garnet Group (Silicate Minerals), formula varies e.g., Almandine Fe3Al2(SiO4)3
mineral
Quartz (Milky/Gravel variety)
Silicon Dioxide (SiO2)
mineral
Natural Gemstone Cabochons (Ruby, Moonstone, Emerald, Citrine)
Ruby (Al2O3:Cr), Moonstone (KAlSi3O8), Emerald (Be3Al2(SiO3)6:Cr), Citrine (SiO2)
mineral
Citrine Quartz
Crystalline Silicon Dioxide (SiO2) with Ferric Iron impurities
mineral
Mica Schist
Mica Schist (primarily Muscovite or Biotite sheet silicates)
metamorphic
Petrified Wood (Silicified Wood)
Silicified Paleoflora (mainly Quartz, SiO2)
metamorphic
Grey Slate
Foliated Metamorphic Rock (formed by low-grade regional metamorphism of shale or mudstone)
metamorphic