Rough Diamond
Diamond (C)
Category
Browse sedimentary (volcanic) specimens identified by the Rock Identifier community.
Rough Diamond
Diamond (C)
Diorite
Plutonic Igneous Rock (Intermediate Composition)
Mixed Mineral Specimens
Mixed Silicates, Oxides, and Phosphates (SiO₂, Ca₅(PO₄)₃(F,Cl,OH), Na₈Al₆Si₆O₂₄Cl₂, etc.)
Agate (Beads)
Silicon Dioxide (SiO2)
Diamond (in jewelry setting)
Diamond (C - Carbon)
Carnelian
Silicon Dioxide (SiO2) - variety of Chalcedony
Diamond (or Lab-Grown Cubic Zirconia)
Carbon (C)
Agate (specifically Botswana or Lake Superior style chalcedony)
Silicon Dioxide (SiO2)
Diorite
Phaneritic plutonic rock (dominated by plagioclase feldspar and hornblende)
Blue Lace Agate (Heat-treated/Crackle Quartz variety)
Silicon Dioxide (SiO2)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Orca Agate
Chalcedony (Microcrystalline Quartz, SiO2)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Prehnite
Prehnite - Ca2Al(AlSi3O10)(OH)2
Sandstone or Limestone
Arenite or Calcareous Sedimentary Rock
Sandstone
Arenite (Clastic Sedimentary Rock)
Sandstone (Ferruginous)
Arenite (Siliclastic Sedimentary Rock)
Agate
Silicon Dioxide (SiO2)
Basalt
Extrusive mafic rock (Basalt)
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Orange Quartz
Silicon Dioxide (SiO2)
Pumice
Pumice (a highly vesicular extrusive igneous rock, primarily amorphous silica)
Basalt with vesicles (Amygdaloidal Basalt)
Amygdaloidal Basalt (predominantly Plagioclase and Pyroxene)
Porphyry
Porphyritic Rhyolite or Andesite
Peridotite (Dunite)
Peridotite (mostly Olivine: (Mg,Fe)2SiO4)
Basalt with Quartz/Calcite matrix
Basalt (SiO2 with Ca/Mg/Fe silicates) on a Mineral Matrix
Amygdaloidal Basalt
Amygdaloidal Basalt (with secondary mineral infilling)
Vesicular Basalt
Basalt with secondary mineral infilling (Amygdaloidal Basalt)
Porphyry (Flower Stone)
Porphyritic Basalt or Andesite
Basalt (Lava Rock) and Dyed Glass/Quartz
Scoria (Vesicular Basalt)
Amethyst
Silicon Dioxide (SiO2) with trivalent iron (Fe3+) impurities
Basalt with Vesicular Texture (Beach Cobble)
Vesicular Basalt (Aphanitic Igneous Rock)
Carnelian Agate
Silicon Dioxide (SiO2) with high Iron Oxide impurities
Porphyritic Basalt
Basalt with plagioclase phenocrysts
Agate
Silicon Dioxide (SiO2)
Vesicular Basalt
Extrusive mafic igneous rock (primarily Plagioclase Feldspar and Pyroxene)
Yellow Quartz (Chalcedony)
Quartz / Chalcedony (Silicon Dioxide, SiO2)
Quartz (Beach Pebble)
Quartz (Silicon Dioxide - SiO2)
Agate (specifically a Thunderegg/Agate Nodule)
Cryptocrystalline Quartz (SiO2)
Banded Rhyolite (likely Green Jasper/Agate variety)
Silicon Dioxide (SiO2) with mineral inclusions
Diabase (Dolerite) Cobble
Diabase / Dolerite