Granite
Intrusive igneous rock
Category
Browse mineral (impactite) specimens identified by the Rock Identifier community.
Granite
Intrusive igneous rock
Gneiss
Gneiss
Geode half
Geode (often quartz/chalcedony based)
Pyrite
Iron Sulfide (FeS2)
Quartz-rich pegmatite (milky quartz with feldspar)
Quartz (SiO₂)–feldspar pegmatite, likely containing albite or orthoclase
Apatite
Ca5(PO4)3(F,Cl,OH)
Rainbow Fluorite
Calcium Fluoride (CaF2)
Fluorite
Calcium Fluoride (CaF2)
Apatite
Fluorapatite, Chlorapatite, and Hydroxylapatite (Ca5(PO4)3(F,Cl,OH))
Likely fluorescent mineral specimen
Uncertain; possibly willemite (Zn₂SiO₄) or fluorite (CaF₂)
Hemimorphite
Hemimorphite (Zn4Si2O7(OH)2·H2O)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Serpentine (likely antigorite-rich serpentinite fragment)
Serpentine-group minerals, chiefly Mg₃Si₂O₅(OH)₄
Gravel and Sediment Sample
Mixed clastic sediment
Green serpentine-rich rock (possibly serpentinite)
Serpentinite, composed chiefly of serpentine-group minerals (e.g., lizardite, antigorite, or chrysotile)
Potassium Feldspar
Orthoclase (KAlSi3O8)
Pink Feldspar (Orthoclase)
Orthoclase Feldspar (KAlSi3O8)
Granite
Granite, a coarse-grained intrusive felsic rock composed mainly of quartz, feldspar, and mica
Vesicular Basalt / Scoria pebble
Extrusive igneous rock with amygdaloidal infilling
Likely faceted garnet
Garnet group, commonly almandine (Fe₃Al₂(SiO₄)₃); identification from the photo is uncertain
Blue Apatite
Ca5(PO4)3(F,Cl,OH)
Satin Spar (Gypsum)
Calcium Sulfate Dihydrate (CaSO4·2H2O)
Limonite / Ironstone
Limonite (Hydrated Iron Oxide) - FeO(OH)·nH2O
Weathered rock pebble, possibly quartz-rich sandstone
Uncertain from the image; likely quartz-bearing sandstone with iron-oxide staining
Hematite
Iron(III) oxide (Fe2O3)
Quartz-rich rock, likely granite or quartz-bearing metamorphic rock
Undetermined; possibly granitic rock composed mainly of quartz and feldspar, with mica or other dark minerals
Unidentified small mineral specimen
Undetermined from the image
Fossilized Shark Tooth
Chondrichthyes (Class)
Shark Tooth Fossil
Chondrichthyes (class) fossilized tooth
Amethyst
Quartz (Silicon Dioxide, SiO2)
Chrysocolla on Matrix
Hydrated copper silicates ((Cu,Al)2H2Si2O5(OH)4·nH2O)
Rhodochrosite
Manganese Carbonate (MnCO3)
Gneiss
Gneiss
Rainbow Fluorite
Fluorite (Calcium Fluoride, CaF2)
Native Copper
Copper (Cu)
Yellow Ochre / Limonite
Hydrated ferric oxide (FeO(OH)·nH2O)
Likely garnet-bearing rock (possibly almandine garnet in matrix)
Garnet, likely almandine (Fe₃Al₂Si₃O₁₂); host rock cannot be determined from the image
Quartz Mineral
Silicon Dioxide (SiO2)
Unknown Rock Fragment
Unknown
Banded gneiss pebble
Feldspar–quartz gneiss; exact mineral composition cannot be confirmed from the image
Drill Core Samples (Varied Lithology)
Multi-lithological core samples (containing potential granite, marble, and phyllite/schist sequence)
Amethyst
Amethyst (Silicon Dioxide, SiO2)