Black Tourmaline
Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)
mineral
Category
Sedimentary Rock Or Mineral (Depending On Origin And Purity)
Browse sedimentary rock or mineral (depending on origin and purity) specimens identified by the Rock Identifier community.
Quartz
Quartz (Silicon Dioxide, SiO2)
Mineral
Sandstone (with Iron Staining)
Clastic sedimentary rock (SiO2 with Fe2O3 oxides)
sedimentary
Quartzite
Quartzite (SiO2)
metamorphic
Serpentine
Serpentinite (rock), Serpentine group minerals (e.g., Antigorite, Lizardite, Chrysotile)
Metamorphic rock
Red Sandstone
Arenite (primarily Quartz with Iron Oxide)
sedimentary
Quartz (Fieldstone/Pebble)
Silicon Dioxide (SiO2)
mineral
Sandstone
Clastic Sedimentary Rock (composed mostly of SiO2)
sedimentary
Sandstone (Ferruginous)
Arenite with Iron Oxide (Limonite/Hematite) coating
sedimentary
Serpentinite (Serpentine Rock)
Primarily composed of serpentine group minerals, such as antigorite, chrysotile, and lizardite. Chemical formula for serpentine minerals is (Mg,Fe)3Si2O5(OH)4.
Metamorphic
Quartzite Pebble
Quartzite (primarily SiO2)
metamorphic
Quartzite
Quartzite (Primary mineral: Quartz, SiO2)
metamorphic
Sandstone
Arenite (general term for sandstone)
Sedimentary Rock
Goldstone
N/A (Synthetic Glass with Copper Inclusions)
Manufactured Glass
Chalcedony Nodule in Matrix
Silicon Dioxide (SiO2)
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
Mineral / Sedimentary
Ironstone Concretion (Limonite/Hematite Nodules)
Ironstone (principally Limonite FeO(OH)·nH2O or Hematite Fe2O3 mixed with silica/clay)
sedimentary
Banded Jasper (possibly "Picture Jasper")
Jasper (a microcrystalline variety of Quartz / Silicon Dioxide - SiO2)
Sedimentary rock (specifically a chemical sedimentary rock, or a chert if considered purely mineral aggregate)
Pyrite
Pyrite (FeS₂)
Mineral
Quartzite
Quartzite (SiO2-dominant rock)
metamorphic
Fossilized Horn Coral
Rugosa
fossil
Sandstone
Arenite
sedimentary
Snowflake Obsidian
Volcanic glass with Cristobalite inclusions (70–75% SiO2)
igneous
Banded Calcite (often sold as Mexican Onyx or Aragonite)
Calcite/Aragonite (Calcium Carbonate, CaCO3)
sedimentary
Quartzite
Quartzite (SiO2)
Metamorphic
Sandstone (likely Arkosic)
Clastic Sedimentary Rock
sedimentary
Sandstone (likely Siltstone or fine-grained Sandstone)
Sedimentary Rock (Clastic)
sedimentary
Quartzite Pebble
Quartzite (SiO2)
metamorphic
Sandstone (Quartzose)
Arenite (primarily SiO2)
sedimentary
Quartz (Druzy)
Silicon Dioxide (SiO2)
mineral
Sandstone (lithic wacke)
Arenite / Lithic Wacke (mostly SiO2 with rock fragments)
sedimentary
Fluorite
Fluorite (Calcium Fluoride, CaF2)
mineral
Diamond (in a cluster setting)
Crystallized Carbon (C)
mineral
Ferruginous Quartz
Silicon Dioxide with Hematite/Limonite inclusions (SiO2 + Fe2O3)
mineral
Sunstone (variety of Feldspar)
Oligoclase Sunstone, Plagioclase Feldspar (Na,Ca)Al(Si,Al)Si2O8
Mineral
Quartz
Silicon Dioxide (SiO2)
Mineral
Quartz (Druzy)
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Jade
There are two distinct minerals commonly known as Jade: Jadeite (NaAlSi2O6) and Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2). Based on the appearance, these spheres are likely Nephrite.
Mineral
Veined Quartz
SiO2 (Silicon Dioxide)
Mineral
Granite (specifically Pink or Red Granite)
Phaneritic Felsic Igneous Rock (Granite)
igneous
River Rock (likely Siltstone or fine-grained Sandstone)
Clastic Sedimentary Rock
sedimentary