Green Calcite
Calcium Carbonate (CaCO3)
Category
Browse metamorphic or igneous alteration specimens identified by the Rock Identifier community.
Green Calcite
Calcium Carbonate (CaCO3)
Smoky Quartz (with Druzy/Polished Edge)
Smoky Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz (Water-Worn Pebble)
Silicon Dioxide (SiO2)
Pyrite
Iron Sulfide (FeS2)
Smoky Quartz
Silicon Dioxide (SiO2)
Hematite
Iron(III) oxide (Fe2O3)
Clear Quartz
Silicon Dioxide (SiO2)
Clear Quartz
Silicon Dioxide (SiO2)
Feldspar (Orthoclase/Potassium Feldspar)
KAlSi3O8 (Potassium Aluminum Silicate)
Clear Quartz
Silicon Dioxide (SiO2)
Sodalite
Sodium Aluminum Silicate Chloride (Na8(Al6Si6O24)Cl2)
Quartz (Milky and Bull Quartz)
Silicon Dioxide (SiO2)
Citrine
Silicon Dioxide (SiO2) with iron impurities
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Quartz (Iron-Stained or Milky Quartz)
Silicon Dioxide (SiO2)
Hematite
Iron(III) oxide (Fe2O3)
White Moonstone (Feldspar)
Potassium aluminum silicate (KAlSi3O8)
Golden Quartz (Citrine or Iron-stained Quartz)
Silicon Dioxide (SiO2)
Garnet
Garnet Group (Silicate Minerals), formula varies e.g., Almandine Fe3Al2(SiO4)3
Blue Star Sapphire
Corundum (Al2O3)
Ruby
Corundum (Al2O3 with Chromium impurities)
Feldspathic Gneiss (Granite Gneiss)
Gneiss (High-grade Regional Metamorphic Rock)
Quartz on Chlorite Schist
Chlorite Schist (Mg,Fe)3(Si,Al)4O10(OH)2 with Quartz (SiO2)
Gneiss
Gneiss (Metamorphic rock composed primarily of quartz, feldspar, and mica)
Veined Quartz
SiO2 (Silicon Dioxide)
Serpentinite (Serpentine Rock)
Serpentinite is a rock composed of one or more serpentine group minerals, chiefly antigorite, chrysotile, and lizardite, with the general formula (Mg,Fe)3Si2O5(OH)4. Often includes other minerals like magnetite, talc, and chromite.
Star Sapphire
Corundum (Al2O3) with Rutile inclusions
River Quartz Cobble
Silicon Dioxide (SiO2)
Nuummite
Nuummite (Orthoamphibole rock composed of Anthophyllite and Gedrite, (Mg,Fe)7Si8O22(OH)2)
Marble
Metamorphosed Limestone (mainly CaCO3)
Quartz (beads)
SiO2 (Silicon Dioxide)
Gossan (Iron Hat)
Limonitic Gossan (Fe-oxide/hydroxide complex)
Milky Quartz
Quartz / Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Gneiss
Gneissic Metamorphic Rock
Banded Gneiss
Gneiss (Metamorphic Rock)
Gneiss with Quartz/Feldspar Vein
Quartz-Feldspathic Gneiss
Milky Quartz with Iron Staining
Quartz (Silicon Dioxide, SiO2)
Quartz (Iron-Stained)
Silicon Dioxide (SiO2)
Gneiss
High-grade Metamorphic Gneiss
Greenstone (Epidote/Chlorite Rich Rock)
Metabasalt (often contains Epidote Ca2Al2(Fe3+;Al)(SiO4)(Si2O7)O(OH))