Amethyst Geode
Quartz (Silicon Dioxide, SiO2)
Category
Browse organic (geological interest) specimens identified by the Rock Identifier community.
Amethyst Geode
Quartz (Silicon Dioxide, SiO2)
Gneiss
Gneiss (Metamorphic rock)
Quartz (River-worn Pebble)
Quartz (SiO2)
Limestone (Cliff Formation)
Limestone (predominantly CaCO3 as calcite)
Fossiliferous Limestone
Calcium Carbonate (CaCO3) with fossil inclusions
Greenish Metamorphic Rock (likely containing epidote or chlorite)
Metamorphic rock, possibly epidosite or greenstone
Chert (Flint)
Chert (microcrystalline quartz)
Chert
Siliceous sedimentary rock (predominantly microcrystalline quartz, SiO2)
Pink Aragonite
CaCO3
Ferruginous Sandstone with Concretion
Sandstone (SiO2 dominated with Fe2O3 cement)
Calcite
Calcite (CaCO₃)
Flint (Chert Node)
Silicon Dioxide (SiO2)
Chert (Flint)
SiO2 (predominantly microcrystalline or cryptocrystalline quartz)
Chert (Quartz Variety)
Silicon Dioxide (SiO2)
Chert (varieties include Flint or Jasper)
Chert (cryptocrystalline quartz; SiO₂)
Chert
Microcrystalline Quartz (SiO2)
Chert (White Chert)
Silicon Dioxide (SiO2)
Calcite
Calcite (CaCO 3)
Limestone
Sedimentary Rock (Primarily CaCO3)
Lepidolite
K(Li,Al)3(Si,Al)4O10(F,OH)2
Calcite
Calcite (CaCO3)
Sandstone Chert Concretion
Silica-cemented Concretion (primarily SiO2)
Chert Pebble (Jasper variant)
Microcrystalline Quartz (SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Basalt with Epidote (Flowerstone-like texture)
Amygdaloidal Basalt (silicate mineral inclusions)
Chert (Nodule)
Silicon Dioxide (SiO2)
Granite
Granite (a plutonic igneous rock)
Septarian Nodule (Dragon Stone) sphere
Septarian concretion (Calcite, Aragonite, and Limestone)
Chert (Flint variety)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Mookaite Jasper
Siliceous sedimentary rock (variety of Jasper/Chert)
Chert (Nodule)
Silicon Dioxide (SiO2)
Petrified Wood with Lichen
Silicified Wood (SiO2) colonized by crustose lichens
Chert (Nodule)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert (Flint nodule)
Chert (SiO2)
Granite Pebble with Quartz Vein
Granite (Plutonic Igneous Rock) with Quartz (SiO2)
Chert (Iron-Stained)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert (or possibly Flint)
SiO2 (Silicon Dioxide)
Chert (Tan/Yellow variety)
Microcrystalline quartz (SiO2)
Porphyritic Basalt or Porphyritic Andesite
Porphyritic Extrusive Igneous Rock
Ironstone Concretion / Limonite Node
Ferruginous Sedimentary Rock (composed primarily of Limonite FeO(OH)·nH2O and Goethite)
Red Chert (Jasper)
Silicon Dioxide (SiO2)
Chert (with nodule)
Microcrystalline Quartz (SiO2)