Hematite
Hematite (Fe2O3)
Category
Browse anthropogenic (man made artifact) specimens identified by the Rock Identifier community.
Hematite
Hematite (Fe2O3)
Blue Sapphire
Corundum (Al2O3 with trace Titanium and Iron)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Obsidian
Volcanic Glass (SiO2 - Silicon Dioxide with impurities)
Ferruginous Quartz
Quartz (Silicon Dioxide, SiO2) with iron oxide inclusions
Quartz (likely milky/rose quartz variety)
Quartz (SiO2 - Silicon Dioxide)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Quartz Druze
Silicon Dioxide (SiO2)
Banded Agate (specifically Botryoidal/Orbicular Agate)
Silicon Dioxide (SiO2)
Chert (Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Plagioclase Feldspar (specifically Albite/Oligoclase)
(Na,Ca)(Si,Al)4O8
White Precious Opal
Hydrated Silica (SiO2·nH2O)
Granite Pebble (River Rock)
Phaneritic Felsic Igneous Rock
Chert (specifically Yellow or River Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Citrine
Silicon dioxide (SiO2)
Picture Jasper
Silicon Dioxide (SiO2) with iron oxide and clay inclusions
Agate (specifically, likely a geode slice or nodule)
Agate (a variety of Chalcedony, with chemical formula SiO2)
Red Jasper
Jasper (Silicon Dioxide, SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Amber
Succinite (Formula: C10H16O)
Banded Calcite (often sold as 'Mexican Onyx' or 'Green Onyx')
Calcite (Calcium Carbonate, CaCO3)
Hematite
Iron(III) oxide (Fe2O3)
White Quartz Pebble
Quartz (Silicon Dioxide - SiO2)
Coquina / Fossiliferous Limestone
Fossiliferous Calcarenite (Calcium carbonate, CaCO3)
Aquamarine
Beryllium aluminum silicate (Be3Al2Si6O18)
River Pebbles (Sandstone and Quartzite)
SiO2 (Quartz) dominated clastic rocks
Lava Rock (Scoria)
Scoria (highly vesicular basaltic rock)
Chert Nodule (with Flint core)
Sedimentary Cryptocrystalline Quartz (SiO2)
Jasper Agate
Chalcedony (Silicon Dioxide - SiO2)
Quartz (Chert/Chalcedony Variety)
Silicon Dioxide (SiO2)
Pink Feldspar
Orthoclase (KAlSi3O8) or Microcline
Fluorite
Calcium Fluoride (CaF2)
Sandstone (likely Ferruginous)
Arenite (SiO2 with iron oxide impurities)
Milky Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Granite
Phaneritic Intrusive Igneous Rock (primarily composed of SiO2, Al2O3, K2O, Na2O)
Sodalite
Sodalite (Na8Al6Si6O24Cl2)
Emerald In Matrix
Beryl (Be3Al2Si6O18) with trace Chromium/Vanadium
Granite
Phaneritic Igneous Rock (composed primarily of Quartz, Feldspar, and Mica)
Unakite
Epidotized Granite
Quartzite
Quartzite (Primary mineral: Quartz, SiO2)
Petrified Wood
Silicified Wood (primarily Chalcedony/Quartz, SiO2)
Labradorite
Labradorite ((Ca, Na)(Al, Si)4O8)