Clear Quartz (Rock Crystal)
Crystalline Silicon Dioxide (SiO2)
gemstone
Category
Mineral, Possibly Rock Fragment Containing A Mineral
Browse mineral, possibly rock fragment containing a mineral specimens identified by the Rock Identifier community.
Learn about Mineral, Possibly Rock Fragment Containing A Mineral in the encyclopedia
View all →
Sandstone (specifically Arkose or Ferruginous Sandstone)
Sandstone (SiO2 with iron oxide inclusions)
sedimentary
Basalt
Basalt (primarily composed of Plagioclase Feldspar and Pyroxene)
igneous
Shale
Fissile mudstone (primarily clay minerals and silt-sized quartz)
sedimentary
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic Volcanic Rock)
igneous
Amethyst Geode
Silicon Dioxide (SiO2) with iron impurities
mineral
Quartz cluster, possibly druzy quartz on matrix
Quartz (SiO₂), likely microcrystalline to coarse crystalline; associated matrix uncertain
mineral
Basalt
Extrusive igneous rock
igneous
Note: No specimen visible
N/A
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic silicate with secondary mineral inclusions)
Igneous
Quartz (likely Milky Quartz)
Quartz (SiO₂ - Silicon Dioxide)
Mineral
Amygdaloidal Basalt
Amygdaloidal Basalt (extrusive volcanic rock)
Igneous
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic Volcanic Rock)
Igneous
Riverstone (Sandstone Pebble)
Arenite (SiO2 with various lithic fragments)
sedimentary
Sandstone (Quartz Sandstone)
Arenite (primarily SiO2)
sedimentary
Greywacke with Quartz Vein
Greywacke (immature sandstone) with SiO2 inclusions
sedimentary
Herkimer Diamond
Quartz (Silica - SiO2)
mineral
Granite
Felsic intrusive igneous rock
igneous
Sandstone and Conglomerate pebbles
Sedimentary clastic rock
sedimentary
Quartz Geode
Crystalline Silicon Dioxide (SiO2) in a Geodic Concretion
mineral
Amygdaloidal Basalt with Epidote
Amygdaloidal Basalt (Mafic volcanic rock)
igneous
Granodiorite
Granodiorite (containing Plagioclase, Quartz, and Biotite)
igneous
Dendritic Siltstone
Siltstone with Manganese Dendrites (MnO2)
sedimentary
Tumbled metallic sulfide mineral specimen, likely pyrite-bearing ore
Likely pyrite (FeS₂) with associated sulfides and host rock; exact identification requires testing
mineral
Druzy Quartz (part of a Geode)
Silicon Dioxide (SiO2)
mineral
Conical fossil shell or shell fragment
Likely a gastropod shell fragment; exact taxon indeterminate from the image
fossil
Pink Granite (Unakite-bearing or Epidote-bearing Granite)
Plutonic Igneous Rock (Granite)
igneous
Quartz Geode Fragment
Silicon Dioxide (SiO2)
sedimentary
Possible flint or slag fragment
Microcrystalline quartz (chalcedony), or iron-rich industrial slag
mineral
Limestone with Fossil Fragment
Sedimentary carbonate rock (CaCO3)
sedimentary
Metallic sulfide mineral fragment, likely galena
Galena (lead sulfide, PbS), tentative identification
mineral
Turquoise
CuAl6(PO4)4(OH)8·4H2O
mineral
Sandstone (Ferruginous)
Arenite (SiO2 with Iron Oxide impurities)
sedimentary
Gravel and Sand Aggregate
Unconsolidated Clastic Sediment
sedimentary
Banded Gneiss (with possible weathered sulfide or iron staining)
Gneiss, potentially with iron oxide/hydroxide staining (e.g., limonite) or weathered sulfides
Metamorphic
Schist
Mica Schist
metamorphic
Quartz Druzy (Geode Fragment)
Silicon Dioxide (SiO2)
mineral
Weathered granite fragment
Granite; chiefly quartz (SiO₂), feldspar, and mica
igneous
Quartz Druzy (Geode Fragment)
Silicon Dioxide (SiO2)
mineral
Quartz Geode
Silicon Dioxide (SiO2) within a geode
mineral
Schist
Schist (Foliated Metamorphic Rock)
metamorphic
Shale
Laminated Fissile Pelite
sedimentary