Amethyst
Amethyst (Silicon Dioxide, SiO2 + Fe)
mineral
Category
Mineral, Often Found As A Rock
Browse mineral, often found as a rock specimens identified by the Rock Identifier community.
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Tree Agate
Dendritic Agate (Silicon Dioxide, SiO2)
Mineral
Sandstone (likely Quartzose Sandstone)
Arenite (primarily SiO2)
sedimentary
Granite
Plutonic Igneous Rock (composed typically of SiO2, Al2O3, K2O, Na2O, CaO)
igneous
Granite Thin Section
Granitic rock (Phaneritic texture)
igneous
Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Granite
Phaneritic Felsic Igneous Rock (composed of SiO2, KAlSi3O8, NaAlSi3O8)
igneous
Terrazzo (Man-made Composite)
Cementitious or Resin-bound Lithic Composite
sedimentary (artificial)
Red Jasper
Jasper (Silicate mineral - SiO2)
sedimentary
Quartz Druzy Geode Fragment
Silicon Dioxide (SiO2)
mineral
Sandstone (likely Red/Brown Sandstone)
Arenite (SiO2 based)
sedimentary
Crushed Limestone
Calcium Carbonate (CaCO3)
Sedimentary
Gneiss (Cobble)
Gneiss
metamorphic
Stiped Slate Beach Pebble
Low-grade Metamorphic Slate with Quartz Vein (SiO2 on Phyllosilicate base)
metamorphic
Granitic Pegmatite
Pegmatite (Quartz: SiO2, Feldspar: KAlSi3O8, Mica: KAl2(AlSi3O10)(OH)2)
Igneous
Quartz / Milky Quartz
Silicon Dioxide (SiO2)
mineral
Milky Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
mineral
Limonite Concretion
Goethite-rich Concretion (FeO(OH))
sedimentary
Turquoise
CuAl6(PO4)4(OH)8·4H2O (Hydrated copper and aluminum phosphate)
mineral
Sandstone (clastic)
Clastic Sedimentary Rock (primarily composed of SiO2)
sedimentary
Epidote (likely Unakite component or Epidosite)
Epidote (Ca2(Al2Fe)(SiO4)(Si2O7)O(OH))
metamorphic
Carnelian Agate Nodule
Silicon Dioxide (SiO2) - Carnelian Chalcedony
mineral
Rough Corundum (likely Sapphire/Zircon-bearing)
Aluminium Oxide (Al2O3)
mineral
Sandstone (likely Graywacke or Arkose variant)
Clastic Sedimentary Rock (SiO2 with assorted lithic fragments)
sedimentary
Clear Quartz Cluster
Silicon Dioxide (SiO2)
mineral
Quartz (Pebble)
Quartz (SiO₂)
Mineral
Pyrite (on host rock)
Iron Sulfide (FeS2)
mineral
Sandstone Concretion
Clastic sedimentary rock (primarily Quartz SiO2)
sedimentary
Schist
Mica Schist
metamorphic
Galena
Lead Sulfide (PbS)
mineral
Sandstone
Arenite (primarily SiO2)
sedimentary
Sandstone (Weathered Pebble)
Arenite (SiO2 primarily)
sedimentary
Amber
Succinite (Fossilized Tree Resin)
Organic Mineraloid
Amygdaloidal Basalt
Amygdaloidal Mafic Volcanic Rock
igneous
Clear Quartz crystals on a Matrix base (Geode fragment)
Silicon Dioxide (SiO2)
mineral
Basalt with Quartz Veins
Basalt (complex silicate) with Quartz (SiO2) intrusions
igneous
Quartz Veinated Sandstone or Siltstone
Silicon Dioxide (SiO2) within a clastic sedimentary matrix
sedimentary
Iolite-bearing Gneiss (Cordierite)
Cordierite (Mg2Al4Si5O18) in Gneiss matrix
metamorphic
Red Jasper (Siltstone/Quartz variety)
Silicon Dioxide (SiO2) with Hematite impurities
sedimentary
Serpentinite
Serpentinite (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4
metamorphic
Veined Pebble (likely a Quartz-Veined Pebble)
Pebble with Mineral Vein (e.g., Quartz Vein in a Chert/Mudstone Pebble)
Sedimentary Rock (possibly conglomerate or breccia with a quartz vein)