Feldspar
Potassium Feldspar (KAlSi3O8)
mineral
Category
Synthetic (Not A Rock Or Mineral)
Browse synthetic (not a rock or mineral) specimens identified by the Rock Identifier community.
Learn about Synthetic (Not A Rock Or Mineral) in the encyclopedia
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Rhyolite with Lithophysae and Iron Oxide
Extrusive igneous rock / Felsic volcanic rock
igneous
Sandstone
Arenite (SiO2 based)
sedimentary
Geode (Unopened)
Silicon Dioxide (SiO2) in sedimentary host rock
sedimentary
Orbicular Gabbro
Orbicular Gabbro
igneous
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Mixed River Pebbles (including Unakite and Jasper)
Polymineralic geological specimens
igneous and sedimentary
Banded Agate
Cryptocrystalline variety of Quartz (SiO2)
mineral
Granite
Intrusive Igneous Rock
igneous
Granite
Intrusive Igneous Rock
igneous
Basalt with Epidote/Quartz Vein
Mafic Volcanic Rock with Hydrothermal Veining
igneous
Greenstone / altered basalt fragment
Likely chlorite–epidote–actinolite altered basalt; exact identification requires testing
igneous
Sandstone
Sedimentary Rock (Quartz Sandstone)
sedimentary
Foliated Metamorphic Rock (likely Gneiss or Schist)
Gneissic Metamorphic Rock
metamorphic
Jasper and Chalcedony Composite
Silicon Dioxide (SiO2) microcrystalline quartz
sedimentary
Quartz Geode Fragment
Silicon Dioxide (SiO2)
mineral
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic volcanic rock including secondary mineral infills)
Igneous
Pink Granite
Phaneritic Plutonic Felsic Igneous Rock (Granite)
igneous
Quartz Druzy / Quartz Crystal Cluster
Silicon Dioxide (SiO2)
mineral
Gneiss
Gneiss
metamorphic
Quartz (Milky Quartz / Clear Quartz)
Silicon Dioxide (SiO2)
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Ironstone Nodules (Iron Concretion)
Siderite or Hematite Concretion
sedimentary
Sandstone (Banded)
Arenite
sedimentary
Sandstone (Quartz-rich)
Arenite
sedimentary
Schist
Crystalline Metamorphic Rock (Schistose)
metamorphic
Granite
Felsic intrusive igneous rock
igneous
Quartz Geode with Chalcedony
Silicon Dioxide (SiO2) in Geode Form
sedimentary
Sandstone Pebble
Sedimentary Clastic Rock (Quartz Arenite)
sedimentary
Herkimer Diamond
Quartz (Silicon Dioxide, SiO2)
mineral
Sandstone
Sedimentary Clastic Rock (Quartz Arenite)
sedimentary
Brecciated Quartz
Silicon Dioxide (SiO2) with iron oxide cement
sedimentary
Sandstone
Arenite (SiO2 primarily)
sedimentary
Sandstone
Arenite (SiO2 primarily)
sedimentary
Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Basalt
Basalt (extrusive igneous rock)
Igneous
Granite
Felsic intrusive igneous rock
igneous
Granite
Felsic intrusive igneous rock
igneous
Quartz-veined Sandstone Pebble
Quartzite-veined Arenite
sedimentary
Granite Cobble
Granite (Phaneritic Igneous Rock)
igneous
Quartz pebble
Silicon Dioxide (SiO2)
mineral
Gneiss
Gneiss (a type of metamorphic rock)
Metamorphic Rock