Tufa
Calcareous Tufa (CaCO3)
sedimentary
Category
Sedimentary Or Metamorphic (Base Substrate)
Browse sedimentary or metamorphic (base substrate) specimens identified by the Rock Identifier community.
Druzy Quartz
Silicon Dioxide (SiO2)
mineral
Sandstone Beach Pebble
Clastic Sandstone (SiO2 - Quartz-dominant)
sedimentary
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
mineral
Druzy Quartz (on Geode Fragment)
Silicon Dioxide (SiO2)
mineral
White Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Red Sandstone (Old Red Sandstone Pebble)
Arenite with iron oxide (Fe2O3) cement
sedimentary
River Stone (Chert/Siltstone)
Cryptocrystalline Quartz (SiO2) with trace impurities
sedimentary
White Sapphire
Corundum (Al2O3)
mineral
Yellow Aventurine
Silicon Dioxide with inclusions (SiO2 + Muscovite/Fuchsite)
mineral
Note: Item is a Synthetic/Man-made Object
Titanium-coated Stainless Steel (Fe-Cr-Ni-Ti)
Non-geological
Quartz Vein in Sedimentary Matrix
Silicon Dioxide (SiO2) with host rock
mineral
Zoisite with Ruby
Anyolite (Calcium aluminum hydroxy silicate with Corundum) Ca2Al3(SiO4)3(OH)
metamorphic
Aragonite Star Cluster
Aragonite (Calcium Carbonate - CaCO3)
mineral
Milky Quartz with Iron Inclusions
Quartz (Silicon Dioxide, SiO2)
mineral
Red Shale
Lutite (primarily composed of clay minerals and iron oxides like hematite, Fe2O3)
sedimentary
Red Jasper
Jasper (Silicon Dioxide Si₂O₃)
sedimentary
Red Jasper
Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions
sedimentary
Oak-grain Laminate (Industrial/Decorative Furniture Finish)
Melamine Resin-impregnated Decorative Paper on Particleboard (Cellulose/Thermosetting Plastic)
not a rock (synthetic material)
Green Aventurine
Silicon dioxide (SiO2) with fuchsite inclusions
mineral
Jasper (Red and Yellow)
Silicon Dioxide (SiO2) with iron oxide impurities
sedimentary
Red Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
sedimentary
Quartz Vein in Host Rock (Likely Slate or Shale)
Hydrothermal Quartz (SiO2) in Pelitic host rock
metamorphic
Red Jasper
Jasper (Silicon Dioxide, SiO2)
mineral
Laterite
Laterite (Iron/Aluminum-rich oxide)
sedimentary
Potassium-Rich Silicate Clay (inferred from biological context)
Phyllosilicate group (likely Illite or Smectite within surrounding soil substrate)
mineral
Unidentifiable Rock Fragment
Uncertain
Yellow Agate
Agate (Varietal form of Chalcedony/Quartz, SiO2)
mineral
Milky Quartz Vein in Host Rock
Silicon Dioxide (SiO2)
mineral
Granite Pebble (River Rock)
Phaneritic Felsic Igneous Rock
igneous
Ferruginous Quartz
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
mineral
Sandstone (Quartzose Pebble)
Clastic Sedimentary Rock (Litharenite/Quartz arenite)
sedimentary
Red Jasper
Jasper (Silicon Dioxide with Iron Oxide inclusions, SiO2)
sedimentary
Amethyst and Gravel Collection
Amethyst (Silicon Dioxide, SiO2)
mineral
Iolite (Cordierite)
Magnesium Iron Aluminum Silicate (Mg,Fe)2Al4Si5O18
mineral
Limonite after Pyrite (Prophecy Stone or Ironstone Concretion)
Goethite/Limonite pseudomorph after Pyrite/Marcasite (FeO(OH)·nH2O)
mineral
Red Jasper
Silicon Dioxide (SiO2) with Hematite impurities
mineral
Jasper Conglomerate (Puddingstone)
Siliceous Conglomerate (Quartz and Jasper clasts in a fine-grained matrix)
sedimentary
Amethyst and Hematite Bracelet
Amethyst (SiO2) and Hematite (Fe2O3)
mineral
Green Opal
Hydrated Silica (SiO2·nH2O)
mineraloid
Jasper (Red Jasper)
Silicon Dioxide (SiO₂)
sedimentary
Iolite-bearing Gneiss (Cordierite)
Cordierite (Mg2Al4Si5O18) in Gneiss matrix
metamorphic