Diorite
Diorite (Intermediate intrusive igneous rock)
Category
Browse organic gemstone (not a rock or mineral) specimens identified by the Rock Identifier community.
Diorite
Diorite (Intermediate intrusive igneous rock)
Granite Gneiss
Gneiss (High-grade Metamorphic Rock)
Gneiss
Gneiss (high-grade metamorphic rock)
Quartz in Matrix (possibly with Biotite or Hornblende)
Quartz (Silicon Dioxide, SiO2) in Granitic Matrix
Bauxite
Bauxite (Mixture of Al(OH)3, AlO(OH), and Fe2O3)
Shale
Shale (Consolidated fine-grained clay/silt)
Amber
(C10H16O)n – an amorphous organic substance, primarily composed of polymerized isoprenoids.
Limestone
Calcium Carbonate (CaCO3)
Diamond (Cluster Ring)
Carbon (C)
Diamond
Native Carbon (C)
Amethyst
Amethyst (Silicon Dioxide - SiO2 with Iron impurities)
Almandine Garnet (weathered)
Almandine (Fe3Al2(SiO4)3)
Garnet and Quartz
Pyrope or Almandine (Red Garnets) and Quartz (Center Stone)
Quartz (Crystal Fragment)
Quartz / Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Quartz (Pale Rose or Milky Variety)
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Red Garnet
Almandine Garnet (Fe3Al2(SiO4)3)
Rose Quartz
Silicon Dioxide (SiO2)
Lake Superior Agate
Silicon Dioxide (SiO2) - Variety Agate
Rough Quartz (likely Rose or Smoky variant)
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Carnelian
Cryptocrystalline Quartz (SiO2)
Chrysoprase
Silicon dioxide (SiO2) with nickel impurities
Amethyst (Faceted)
Quartz (SiO2) with iron impurities
Quartz (Water-worn pebble)
Silicon Dioxide (SiO2)
Quartz (Milky/Gray variety)
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Sodalite
Sodalite [Na8(Al6Si6O24)Cl2]
Smoky Quartz
Silicon Dioxide (SiO2)
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) within Sedimentary or Igneous Matrix
Sandstone
Arenite (composed primarily of SiO2)
Carnelian (Chalcedony)
Silicon Dioxide (SiO2)
Sunstone (Feldspar variety)
Oligoclase or Andesine (Na,Ca)(Al,Si)4O8
Basalt with Quartz/Calcite matrix
Basalt (SiO2 with Ca/Mg/Fe silicates) on a Mineral Matrix
Banded Gneiss
Gneiss (High-grade metamorphic rock)
Quartz (Citrine or Iron-Stained)
Silicon Dioxide (SiO2)
Peridot (Olivine)
Olivine (Magnesium Iron Silicate - (Mg, Fe)2SiO4)
Basalt
Basalt (Mafic volcanic rock)
Basalt
Basalt (primarily composed of Plagioclase Feldspar and Pyroxene)