Amygdaloidal Basalt
Amygdaloidal Basalt (containing quartz/agate or zeolite fill)
Category
Browse mineral specimens identified by the Rock Identifier community.
Amygdaloidal Basalt
Amygdaloidal Basalt (containing quartz/agate or zeolite fill)
Granite
Intrusive Igneous Rock
Shale
Shale (clastic sedimentary rock)
Quartz on Schist
Silicon Dioxide (SiO2) on Foliated Metamorphic Rock
Quartz-rich hydrothermal mineral specimen, possibly vanadinite-bearing matrix
Quartz (SiO₂) with unidentified red-brown accessory minerals; exact species requires testing
Granite
Intrusive igneous felsic rock
Greenschist
Chlorite Schist (Greenschist Facies)
Black Sand (Magnetite/Heavy Mineral Concentrate)
Magnetite-rich Placers (Fe3O4)
Limonite pseudo-concretion (Ironstone)
Limonite (FeO(OH)·nH2O) / Goethite
Milky quartz cluster
Quartz, silicon dioxide (SiO₂)
Quartz Pebble
Quartz (Silicon Dioxide - SiO2)
Limonite Stained Basalt
Hydrated Iron Oxide on Mafic Volcanic Rock (FeO(OH)·nH2O)
Limonite (Ironstone)
Limonite (FeO(OH)·nH2O)
Blue Apatite
Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)
Chalcedony (Botryoidal)
Silicon Dioxide (SiO2)
Quartz–calcite sulfide-bearing mineral specimen
Quartz (SiO₂) with likely calcite (CaCO₃) and iron sulfides, possibly pyrite (FeS₂); exact species requires testing
Turquoise
Turquoise, CuAl6(PO4)4(OH)8·4H2O
Copper Ore
Cupriferous Rock / Mixed Mineral Matrix
Sandstone with Manganese Dendrites
Clastic Sedimentary Rock (SiO2 based with MnO2 inclusions)
Calcite (commonly referred to as Orange Calcite or Honey Calcite given its color)
Calcite
Polished greenstone (likely serpentine)
Serpentinite; chiefly serpentine-group minerals, Mg₃Si₂O₅(OH)₄
Granite
Granite (Plutonic Igneous Rock)
Granitic Gneiss
Gneiss (Metamorphic rock of granitic composition)
Gneiss
Gneiss (Metamorphic rock)
Granite
Phaneritic Plutonic Felsic Rock (SiO2, KAlSi3O8, NaAlSi3O8, CaAl2Si2O8)
Fluorite
Calcium fluoride (CaF2)
Gneiss (Cobble)
Gneiss
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Quartz-rich pegmatite fragment
Granite-family pegmatite; chiefly quartz (SiO₂), feldspar, and black mica (biotite)
Travertine
Calcium Carbonate (CaCO3)
Limonite (Yellow Ochre)
Hydrated iron(III) oxide-hydroxides (FeO(OH)·nH2O)
Limonite (Iron Ore)
Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)
Milky Quartz with Mica Matrix
SiO2 (Silicon Dioxide) with Muscovite/Biotite mica
Prehnite
Prehnite (Ca2Al2Si3O10(OH)2)
Raw greenish-blue quartz-bearing mineral specimen
Likely fluorite or chalcedony/quartz; exact identification requires hardness and crystal tests
Olivine (Peridot)
Magnesium Iron Silicate (Mg,Fe)2SiO4
Quartz Mineral
Silicon Dioxide (SiO2)
Gold Mineral
Native Gold (Au)
Quartz-rich pegmatite fragment
Granite/pegmatite; chiefly quartz (SiO₂) and feldspar, with possible biotite or tourmaline
Fossil Shark Tooth
Carcharocles (Otodus) sp. or similar fossilized Chondrichthyes tooth
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Fluorite (specifically Blue John or Banded Fluorite)
Calcium Fluoride (CaF2)