Basalt (River Stone)
Basalt
Category
Browse sedimentary (volcanic) specimens identified by the Rock Identifier community.
Basalt (River Stone)
Basalt
Milky Quartz
Silicon Dioxide (SiO2)
Basalt
Mafic extrusive igneous rock
Basalt
Basalt
Diorite (River Cobble)
Intermediate plutonic igneous rock
Basalt (with possible Olivine inclusions)
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Basalt
Basalt (Extrusive Mafic Igneous Rock)
Agate
Silicon Dioxide (SiO2) - variety of Chalcedony
Basalt (River Stone)
Basalt (Mafic Extrusive Igneous Rock)
Agate (Moss or Dendritic Agate)
Chalcedony (Silicon Dioxide, SiO2)
Limonite / Ironstone Nodule
Limonite (Hydrated iron(III) oxide-hydroxide), FeO(OH)·nH2O
Banded Agate (specifically shades of Carnelian Agate)
Silicon Dioxide (SiO2)
Purple Dyed Agate Geode (Banded Chalcedony)
Silicon Dioxide (SiO2) - variety: Agate
Agate (specifically Oco or Banded Agate)
Agate (a variety of Chalcedony), SiO2 (Silicon Dioxide)
Chert (often called Flint when dark)
Sedimentary cryptocrystalline quartz (SiO2)
Stilbite
Stilbite-Ca (NaCa4Mg[Al9Si27O72]·28H2O)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Turquoise
Turquoise (CuAl6(PO4)4(OH)8·4H2O)
Diorite (River Rock/Cobble)
Intermediate Plutonic Igneous Rock (Diorite)
Diamond
Diamond (pure Carbon, C)
Diorite
Diorite (Intermediate intrusive igneous rock)
Dzi Bead (Etched Chalcedony)
Cryptocrystalline Quartz (SiO2) with chemical etching
Diamond (in a jewelry setting)
Diamond (Carbon, C)
Amethyst (Geode)
Silicon Dioxide (SiO2) with iron impurities
Black Onyx
Silicon Dioxide (SiO2)
Diorite
Diorite (Intermediate intrusive igneous rock)
Banded Agate (Crazy Lace/Mexican Agate Variety)
Silicon Dioxide (SiO2)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Diamond
Carbon (C)
Diamond
C (Carbon)
Amethyst
SiO2 (Silicon Dioxide)
Amethyst
Silicon Dioxide (SiO2) with traces of Iron and Manganese
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Amethyst Quartz
Silicon Dioxide (SiO2)
Gold
Native Gold (Au)
Gold Nugget
Native Gold (Au)
Tree Agate
Silicon Dioxide (SiO2) with Dendritic Inclusions
Basalt Cobble
Aphanitic Mafic Igneous Rock (Basalt)
Peridot (Olivine)
Magnesium Iron Silicate (Mg, Fe)2SiO4
Agate (Bead Form)
Agate (Cryptocrystalline Quartz, SiO2)
Pumice
Pumice (Vesicular Rhyolite/Andesite)