Hematite
Iron(III) oxide (Fe2O3)
Category
Browse igneous, sedimentary, metamorphic, and mineral specimens identified by the Rock Identifier community.
Hematite
Iron(III) oxide (Fe2O3)
Diorite (Dalmatian Stone)
Phaneritic Plutonic Diorite
Muscovite on Quartz (Mica host rock)
KAl2(AlSi3O10)(OH)2 (Muscovite) in SiO2 (Quartz)
Pyrite in Matrix (Commonly called Fool's Gold)
Iron Sulfide (FeS2)
Limonite Pseudomorph after Pyrite
Goethite/Limonite FeO(OH)·nH2O replacing Pyrite FeS2
Ruby in Zoisite
Anyolite (Calcium Aluminum Silicate with Aluminum Oxide impurities)
Blue Aventurine
Silicon Dioxide (SiO2) containing Dumortierite or Crocidolite inclusions
Yellow Jade (often Serpentine or Dolomite)
Primarily Serpentine (Mg3Si2O5(OH)4) or Dolomite (CaMg(CO3)2), though the term 'yellow jade' is also sometimes applied to varieties of true nephrite or jadeite.
Blue Chalcedony
Silicon Dioxide (SiO2)
Ferruginous Quartz
Silicon Dioxide with Iron Oxide (SiO2 + Fe2O3)
White Jade / White Chalcedony
Nephrite Jade (Ca2(Mg,Fe)5Si8O22(OH)2) or Chalcedony (SiO2)
Granite Sand (Decomposed Granite)
Grus / Quartz-Feldspar Detritus
Botryoidal Chalcedony (Agate/Desert Rose Chalcedony)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Ruby in Zoisite
Ruby (α-Al2O3) embedded in Zoisite (Ca2Al3(SiO4)3(OH)) with some Hornblende
Mica Schist with Iron Staining
Mica Schist
Green Slate (Greenstone)
Foliated Metamorphic Rock (rich in Chlorite/Epidote)
Ruby
Corundum (Al2O3 with chromium impurities)
Phyllite
Phyllite (Intermediate grade metamorphic rock)
Milky or Greenish Quartz Pebble
Silicon Dioxide (SiO2)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Crackle Agate / Dyed Quartz
SiO2 (Silicon Dioxide)
Quartz Drusy on Matrix
Silicon Dioxide (SiO2)
Banded Calcite (often sold as Mexican Onyx)
Calcium Carbonate (CaCO3)
White Agate (Chalcedony)
Chalcedony (SiO2)
Carnelian
Carnelian (Silicon Dioxide, SiO2)
Chalcedony (Agate)
Silicon Dioxide (SiO2)
White Marble
Recrystallized Calcite (CaCO3)
Seraphinite (Clinochlore)
Clinochlore (Mg,Fe2+)5Al(Si3Al)O10(OH)8
Dyed Pink Agate Slice
Cryptocrystalline variety of Quartz (SiO2)
Carnelian
Carnelian (a variety of Chalcedony, SiO2)
Galena
Lead Sulfide (PbS)
Quartz Druzy (on Calcedony/Quartz base)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified wood (primarily Silicon Dioxide, SiO2)
Granite
Granite
Quartz Geode (Nodule)
Silicon Dioxide (SiO2)
Quartz / Limestone Gravel
SiO2 (Silicon Dioxide) and CaCO3 (Calcium Carbonate)
Agate
Banded Chalcedony (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Hematite impurities
Calcite
Calcium Carbonate (CaCO3)
Emerald
Beryl (Be3Al2(SiO3)6) with Chromium/Vanadium impurities
Unakite
Epidotized Granite
Garnet in Matrix
Almandine or Spessartine Garnet in Quartz/Schist Matrix (X3Al2(SiO4)3)