Basalt
Basalt (Mafic volcanic rock)
Category
Browse industrial byproduct specimens identified by the Rock Identifier community.
Basalt
Basalt (Mafic volcanic rock)
Sapphire
Corundum (Al2O3)
Agate and Amethyst (Quartz variants)
Silicon Dioxide (SiO2) - Microcrystalline Quartz and Crystalline Quartz
Chert (and Flint variant)
Microcrystalline Quartz (SiO2)
Banded Agate (specifically Sardonyx)
Silicon Dioxide (SiO2) - variety of Chalcedony/Quartz
Quartzite (Iron-stained)
Metamorphosed Quartz-rich Rock (SiO2)
Red Quartzite
Quartzite (primarily SiO2 with hematite inclusions)
Sandstone Moqui Marble (Concretion)
Iron oxide concretion (Hematite/Goethite and Quartz)
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Anthracite
Anthracite Coal
Chert (often called Flint)
Chert (Microcrystalline Silicon Dioxide, SiO2)
Mica Schist
Mica Schist (primarily Muscovite and Biotite composition)
Clear Quartz (Rock Crystal)
Quartz (Silicon Dioxide - SiO2)
Milk Quartz (White) and Yellow Aventurine (Yellow)
Silicon Dioxide (SiO2)
Magnetite (Lodestone)
Magnetite (Fe3O4)
Quartz Pebble
Silicon Dioxide (SiO2)
Chert (specifically Flint or Common Opal variant)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Corundum (Ruby/Sapphire crystal)
Al2O3 (Aluminum Oxide)
Chert (specifically Gray/Black Chert)
Chert (Microcrystalline or Cryptocrystalline Quartz, SiO2)
Chert Nodule (Flint)
Microcrystalline Quartz (SiO2)
Olivine (Peridot in gem form)
Magnesium Iron Silicate (Mg,Fe)2SiO4
Agate
Silicon Dioxide / Cryptocrystalline Quartz (SiO2)
Chert (specifically Gray/Blue-Gray Chert)
Chert (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Iron inclusions
Green Fluorite
Fluorite (Calcium Fluoride - CaF2)
Milky Quartz with Mineral Inclusions
Silicon Dioxide (SiO2)
Quartzite
Quartzite (primarily SiO2)
Botryoidal Chalcedony (Desert Rose / Grape Agate variant)
Silicon Dioxide (SiO2)
Ferruginous Quartz
Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Precious Opal
Hydrated Silica (SiO2·nH2O)
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Agate (Grey Agate Slice)
Microcrystalline Quartz (SiO2)
Anthracite Coal
Anthracite (Carbon)
Mica Schist
Mica Schist (primarily Muscovite or Biotite sheet silicates)
Schist
Mica Schist
Rose Quartz and Milky Quartz
Silicon Dioxide (SiO2)
Chert (specifically Blue Chert/Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Rough Corundum (likely Sapphire/Zircon-bearing)
Aluminium Oxide (Al2O3)
Rose Quartz with Feldspar Inclusions
Silicon Dioxide (SiO2)
Quartz with Hematite Inclusions
Silicon Dioxide (SiO2) with Ferric Oxide (Fe2O3)
Quartzite
Quartzite (primarily SiO2)