Diamond
Diamond (pure carbon C)
Category
Browse antropogenic (man made glass byproduct) specimens identified by the Rock Identifier community.
Diamond
Diamond (pure carbon C)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Banded Chert / Banded Jasper (likely a variety of Chert/Chalcedony)
Chert (microcrystalline quartz)
Peridot (likely, based on color and appearance)
Olivine group mineral, specifically (Mg,Fe)2SiO4 (Forsterite-Fayalite solid solution series)
Chert (Flint)
Chert (predominantly SiO₂ - silicon dioxide)
Quartz (likely) / Siliceous rock with quartz phenocrysts (if a rock fragment)
Quartz (SiO₂)
Quartz (Rock Crystal)
Quartz (SiO₂ - Silicon Dioxide)
Quartz Geode/Druzy Quartz
Quartz (SiO₂)
Fossilized Shell in Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Quartz Geode/Cluster
Quartz (SiO2)
Crystal Quartz Beads (likely Clear Quartz)
Quartz (SiO₂)
Diamond in Kimberlite
Diamond in Kimberlite Matrix (Diamond: C, Kimberlite: complex Potassic Peridotite)
Diamond (in a jewelry setting)
Cubic Carbon (C)
Granite
Granite (Felsic intrusive igneous rock)
Fossilized Coral (Coquina/Limestone)
Cnidaria Anthozoa (Fossilized)
Basalt
Basalt (Mafic volcanic rock)
Orthoclase Feldspar (or K-Feldspar)
Orthoclase (KAlSi3O8)
Pearl
Calcium Carbonate (CaCO3) with Conchiolin
Sapphire (likely blue synthetic sapphire or blue glass in a ring)
Corundum (Al₂O₃), specifically the blue variety due to trace amounts of iron and titanium impurities. If synthetic, it would still be Al₂O₃.
Quartz (Crystal/Druzy Quartz)
Quartz (SiO₂)
Quartzite
Quartzite (primarily SiO2)
Quartz (likely a clear or rock crystal variety)
Quartz (SiO2 - Silicon Dioxide)
Quartz (likely milky/gray variety)
Quartz (SiO₂)
Schist
N/A (a rock type, not a mineral formula)
Diamond
Carbon (C)
Scoria
Scoria (a vesicular basalt or andesite)
Rough Diamond
Pure Carbon (C)
Quartz (variety of colors)
SiO2 (Silicon Dioxide)
Pearl
Aragonite (CaCO3 with conchiolin)
Pebble (likely Quartz or Chert)
SiO₂ (Silicon Dioxide) - referring to the likely main mineral composition, Quartz. If it's chert, the scientific name remains SiO₂ with a microcrystalline structure.
Lepidolite (likely)
K(Li,Al)3(Al,Si)4O10(F,OH)2 (Phyllosilicate mineral, part of the mica group)
Granite
Granite (a common term for a felsic intrusive igneous rock)
Quartzite
Quartzite (SiO2)
Nacre (Mother of Pearl)
Nacre (Biogenic Aragonite/Calcite composite, CaCO3)
Gneiss
Gneiss (a rock type, not a specific mineral with a formula)
Aquamarine and clear quartz
Aquamarine (Be3Al2Si6O18), Quartz (SiO2)
Sandstone
Sandstone (lithified sand)
Chrysoprase
Chrysoprase (a variety of Chalcedony, SiO₂)
Coquina
Bioclastic Limestone (composed primarily of CaCO3)
Chert (specifically White Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Quartz (likely macrocrystalline variety)
Quartz (SiO₂)
Diamond (Cluster Ring)
Carbon (C)