Slate
Metamorphic Pelitic Rock
Category
Browse sedimentary to metamorphic specimens identified by the Rock Identifier community.
Slate
Metamorphic Pelitic Rock
Gneiss
Foliated Metamorphic Rock
Magnetite-rich ironstone (probable magnetite ore)
Magnetite, Fe₃O₄, likely in a fine-grained ironstone matrix
Pyrite
Iron Pyrite (FeS2)
Pyrite (on the right) and Magnetite or Hematite (on the left)
Iron Sulfide (FeS2) and Iron Oxide (Fe3O4 or Fe2O3)
Garnet Gneiss
Garnetiferous quartzo-feldspathic gneiss
Muscovite Schist with Quartz
Mica Schist (KAl2(AlSi3O10)(OH)2)
Rhodonite (in matrix)
Rhodonite (Mn,Fe,Mg,Ca)SiO3
Kyanite
Kyanite (Al2SiO5)
Garnet in Matrix (Schist or Quartz)
Almandine Garnet, Fe3Al2(SiO4)3
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Gneiss
Feldspathic biotite gneiss; a high-grade metamorphic rock composed mainly of quartz, feldspar, and mica
Likely metallic ore specimen
Undetermined; the silvery, reflective surface may indicate specular hematite (Fe₂O₃), but the image is insufficient for reliable identification.
Quartz
SiO2 (Silicon Dioxide)
Quartz
Silicon dioxide (SiO2)
Quartz and Unakite
SiO2 (Quartz) / Epidote, Pink Orthoclase, Quartz (Unakite)
Quartz pebble with iron staining
Silicon dioxide (SiO2) with iron oxide impurities
Magnetite or Hematite Nodule
Iron Oxide (Fe3O4 or Fe2O3)
Calcite
Calcium Carbonate (CaCO3)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Milky Quartz
Silicon Dioxide (SiO2)
Massive White Quartz
Silicon Dioxide (SiO2)
Yellow Quartz
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Orange Quartz / Peach Aventurine
Silicon Dioxide (SiO2)
Magnetite / Lodestone
Magnetite (Fe3O4)
Pyrite
Iron Sulfide (FeS2)
Magnetite / Hematite mix
Magnetite (Fe3O4) and Hematite (Fe2O3)
Orange Calcite
Calcium Carbonate (CaCO3)
White Quartz
Silicon Dioxide (SiO2)
White Quartz
Silicon Dioxide (SiO2)
Raw Calcite
Calcium Carbonate (CaCO3)
Pyrite-bearing Rock
Iron Sulfide (FeS2) associated with host rock
Milky Quartz
Silicon Dioxide (SiO2)
Orange Calcite
Calcium Carbonate (CaCO3)
White Quartz
Silicon Dioxide (SiO2)
Pebble Gravel Mix (Quartzite, Basalt, Chert)
Alluvial River Gravel / Aggregate Clasts
Rough Quartz (Milky / Clear Quartz)
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Tumbled Rose Quartz
Silicon Dioxide (SiO2)