Chert (specifically Flint or Dark Chert)
Chert (SiO2)
Category
Browse organic gem material (botanical) specimens identified by the Rock Identifier community.
Chert (specifically Flint or Dark Chert)
Chert (SiO2)
Coquina Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Piddock bored rock (likely Mudstone or Shale)
Ichnofossil (Gastrochaenolites borings) in Fine-grained Sedimentary Rock
Quartzite Pebble
Quartzite (SiO2 with minor impurities)
Concrete Fragment
Hardened Portland Cement Composite
Nephrite Jade
Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2)
Chert (Yellow Jasper/Quartzite Pebble)
Microcrystalline Silicon Dioxide (SiO2)
Man-made Polished Porcelain Tile (Artificial Geologic Lookalike)
Fused Silicate Ceramic with Alumina (Synthetic Kaolinite derivative)
Chert (variations include Flint/Jasper)
Chert (SiO2)
Granite (Dioritic variant)
Granite (Phaneritic Igneous Rock)
Limestone
Calcium Carbonate (CaCO3)
Chert (Flint)
Silicon Dioxide (SiO2)
Chert (Yellow/Tan variety)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Granite Sand (Decomposed Granite)
Grus / Quartz-Feldspar Detritus
Granite Pebble
Granite (composed primarily of Quartz, Feldspar, and Mica)
Chert (Flint)
Chert (SiO2)
Quartzite Pebble
Metamorphic Quartz (SiO2)
Lava Rock with Fabric Impression
Scoria or Basalt with anthropogenic impressions
White Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Polished Ocean Jasper
Orbicular Jasper (variety of Chalcedony/Quartz, SiO2)
Limonite (Yellow Ochre)
FeO(OH)·nH2O (Hydrous iron(III) oxide-hydroxide mixture)
Limonite (Iron Stone/Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
Cupronickel (on a 1981 Mexico 20 Pesos coin)
Copper-Nickel Alloy (Cu75Ni25)
Slag
Ferrous Slag (Siliceous industrial waste)
Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende, chlorite, or manganese/iron oxides
Fired Clay Brick (Anthropic Rock substitute)
Anthropogenic polycrystalline ceramic (predominantly Mullite and Quartz: Al6Si2O13 + SiO2)
Sandstone (Red/Brown Variety)
Arenite (composed primarily of SiO2 with Fe2O3 iron oxide inclusions)
Chert (Chalcedony/Agate)
Microcrystalline Quartz (SiO2)
Amber
Succinite (fossilized tree resin)
Amethyst Sage Agate
Silicon Dioxide (SiO2) with trace minerals (Manganese/Iron oxides)
Amber (specifically Cherry Amber)
Succinite (with the chemical formula C10H16O)
Diamond
Carbon (C)
Yellow Jasper (Mookaite style)
Silicon Dioxide (SiO2) with Goethite/Hematite inclusions
Rough Citrine Quartz
Silicon Dioxide (SiO2) with iron impurities
Mystic Topaz
Aluminum silicate fluoride hydroxide with titanium coating (Al2SiO4(F,OH)2)
Conglomerate
Conglomerate (clastic sedimentary rock)
Sandstone
Arenite (primarily SiO2)
Sandstone (Quartzose Sandstone)
Arenite
Sandstone (likely Quartzose Sandstone)
Arenite (primarily SiO2)
Banded Gneiss
Gneiss (High-grade Metamorphic Rock)
Sandstone
Arenite
Sandstone
Arenite (composed primarily of SiO2)