Sandstone (likely Arkosic or Quartzose)
Sandstone (SiO2 with inclusions)
Category
Browse the purple specimen is a mineral (amethyst); the white specimen is a sedimentary rock (limestone or marble). specimens identified by the Rock Identifier community.
Sandstone (likely Arkosic or Quartzose)
Sandstone (SiO2 with inclusions)
Blue Chalcedony
Silicon Dioxide (SiO2)
Jasper (likely Brecciated or Multi-colored)
Jasper (SiO2)
Yellow Quartz (Citrine type/Tumbled Quartz)
Silicon Dioxide (SiO2)
Quartzite
Quartzite (SiO2)
Green Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite
Sandstone (Quartzose Sandstone)
Clastic sedimentary rock (primarily SiO2)
Sandstone (Quartzite Pebble)
Arenite / Metamorphosed Sandstone (SiO2)
Sandstone
Arenite (primarily SiO2)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 cementation)
Opal
Hydrated Silica (SiO2·nH2O)
Sandstone
Arenite (composed primarily of SiO2)
Amethyst
Amethyst (Silicon Dioxide, SiO2 + Fe4+ impurities)
Yellow Quartz
Silicon Dioxide (SiO2)
Clear Quartz Cluster
Quartz (Silicon Dioxide - SiO2)
Emerald in Matrix
Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities
Orange Calcite
Calcite (Calcium Carbonate - CaCO3)
Blue Banded Agate (Dyed)
Silicon Dioxide (SiO2) - variety of Chalcedony
Yellow Quartz (Citrine or Quartzite Pebble)
Silicon Dioxide (SiO2)
Amethyst
Silicon dioxide with iron impurities (SiO2 + Fe3+)
Banded Calcite (Cave Onyx)
Calcium Carbonate (CaCO3)
Sandstone (Ferruginous)
Arenite (with Iron Oxides)
Green Quartz (including Prase or Aventurine variants)
Silicon Dioxide (SiO2) with inclusions (likely Actinolite or Chlorite)
Halite (Rock Salt)
Halite (Sodium Chloride, NaCl)
Fossilized Coral
Scleractinia (fossil order), primarily Calcium Carbonate (CaCO3)
Sandstone (River Pebble)
Arenite (primarily SiO2)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Orange Calcite
Calcium Carbonate (CaCO3)
Banded Agate (Onyx variety)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Pink Dyed Agate (Pink Agate Slice)
Silicon Dioxide (SiO2) - Chalcedony / Cryptocrystalline Quartz
Sandstone (Pebble)
Clastic sedimentary rock (SiO2 primary)
Quartz Pebble
Silicon Dioxide (SiO2)
Chert (specifically Iron-stained River Cobble)
Silicon Dioxide (SiO2)
Granite
Granite
Yellow Calcite
Calcium Carbonate (CaCO3)
Blue Calcite
Calcium Carbonate (CaCO3)
Sandstone (Quartzose Sandstone)
Clastic sedimentary rock (SiO2 major component)
Chalcedony (River Stone)
Silicon Dioxide (SiO2)
Granite Gneiss with Garnet
Garnetiferous Gneiss
Quartz with Mica inclusions (likely Schist or Gneiss host)
Silicon Dioxide (SiO2) with Phyllosilicates (KAl2(AlSi3O10)(OH)2)
Amethyst
Amethyst (Silicon Dioxide, SiO2)
Honey Calcite
Calcium Carbonate (CaCO3)