Sandstone Concretion
Arenaceous concretion (primarily SiO2 with Fe2O3 staining)
Category
Browse synthetic or natural fiber specimens identified by the Rock Identifier community.
Sandstone Concretion
Arenaceous concretion (primarily SiO2 with Fe2O3 staining)
Diamond (as set in a gold ring)
Carbon (C)
Smoky Quartz (Tumbled)
Smoky Quartz (SiO2 - Silicon Dioxide)
Smoky Quartz (Tumbled)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Sandstone (Micaceous/Feldspathic variant)
Arenite (specifically subarkose or lithic arenite)
Slate
Foliated Metamorphic Rock (composed primarily of Quartz, Muscovite, and Illite)
Aragonite Star Cluster
Aragonite (Sputnik habit) - CaesarCO3
Dyed Agate Slice
Silicon Dioxide (SiO2) with artificial colorants
Rough Diamond
Diamond (pure Carbon, C)
Blue Sapphire
Corundum (Al2O3 with trace Titanium/Iron)
Diamond (or Diamond Simulant)
Carbon (C)
Granite
Granite (Felsic Plutonic Rock)
Chalcopyrite (Peacock Ore)
Chalcopyrite (CuFeS2)
Amber (and Citrine Quartz)
Succinite (Amber) and Silicon Dioxide (SiO2)
Goldfish Cracker (Culinary Mimic)
Cibus aurum (Commonly composed of Enriched Wheat Flour and Cheddar Cheese)
Pyrite in Shale
Iron Disulfide (FeS2) in Sedimentary Shale
Yellow Quartz (Iron-Stained Quartz)
Silicon Dioxide (SiO2) with iron oxide inclusions
Green Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions (K(Al,Cr)2AlSi3O10(OH)2)
Black Onyx
Silicon Dioxide (SiO2) with cryptocrystalline structure
Amethyst (Rough Quartz)
Silicon Dioxide (SiO2) with iron impurities
Sandstone
Arenite (primarily SiO2)
Carnelian Agate
Carnelian (Silicon Dioxide - SiO2)
Amethyst (Chevron or Banded Amethyst)
Silicon Dioxide (SiO2 with iron impurities)
Jasper
Silicon dioxide / Chalcedony (SiO2)
Clear Quartz
Silicon Dioxide (SiO2)
Gold Nugget
Native Gold (Au)
Red Coral
Corallium rubrum (Calcium Carbonate, CaCO3)
Shale
Fissile mudrock (composed primarily of clay minerals and quartz)
Pink Fluorite
Fluorite (Calcium Fluoride) - CaF2
Coquina / Fossiliferous Limestone
Coquina (composed primarily of Calcium Carbonate / CaCO3)
Natural White Pearl
Calcium Carbonate (Aragonite/Calcite) with Conchiolin - CaCO3
Turquoise
Hydrated phosphate of copper and aluminium: CuAl6(PO4)4(OH)8·4H2O
Titanium Quartz (Rough)
Titanium-included Silicon Dioxide (SiO2 + Ti)
Chert Nodule (with Flint core)
Sedimentary Cryptocrystalline Quartz (SiO2)
Coquina
Biogenic Limestone (Calcite/Aragonite base, CaCO3)
Granite
Phaneritic plutonic rock (dominated by SiO2, Al2O3, K2O, Na2O)
Black Tourmaline
Schorl (Sodium Iron Aluminum Borosilicate Hydroxide), NaFe3Al6(BO3)3Si6O18(OH)4
Smoky Quartz
Silicon Dioxide (SiO2)
Green Aventurine
Aventurine Quartz (SiO2 with inclusions of Fuchsite)
Agate (River Pea)
Microcrystalline Chalcedony (SiO2)
River Jasper (Green Jasper)
Silicon Dioxide (SiO2) with impurities