Cone-in-cone structure
Cone-in-cone structure
Category
Browse not a geological specimen specimens identified by the Rock Identifier community.
Cone-in-cone structure
Cone-in-cone structure
Quartz Crystal Cluster
Silicon Dioxide (SiO2)
Weathered porphyritic volcanic rock
Likely andesite or dacite, with feldspar phenocrysts in a fine-grained groundmass
Decorative mosaic cross containing mixed rock and glass fragments
Polychrome aggregate; likely quartz, feldspar, marble, granite, and assorted colored glass
River Rock (likely Quartzite or Chert)
Quartzite (primarily SiO2)
Corundum (Sapphire in Matrix)
Aluminum Oxide (Al2O3)
Clear Quartz Crystal
Silicon Dioxide (SiO2), Quartz
Quartz Geode with Calcite/Siderite
Crystalline Silicon Dioxide (SiO2) with Carbonate inclusions
Milky Quartz with Iron Staining
Silicon Dioxide (SiO2)
Quartz
Quartz (Silicon Dioxide, SiO2)
Quartz-veined Sandstone Pebble
Quartzite-veined Arenite
Quartz
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Quartz Crystal
Silicon Dioxide (SiO2)
Amethyst
Silicon Dioxide (SiO2)
Quartz (River Cobble)
Silicon Dioxide (SiO2)
Yellow Quartz or Citrine Quartz
Silicon Dioxide (SiO2)
Possible fossilized ammonite or concretion
Indeterminate fossil specimen; possibly an ammonoid mold/cast in iron-rich sedimentary rock
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Generic Pebble / Rock Fragment
Lithic fragment / Weathered rock pebble
Quartz
Silicon Dioxide (SiO2)
Granodiorite Core
Granodiorite
Quartz (Orange/Pink variety)
Silicon Dioxide (SiO2)
Quartz with Iron Staining
Silicon Dioxide (SiO2)
Milky Quartz with Mineral Inclusions
Silicon Dioxide (SiO2)
Quartz Vein in Metamorphic Rock
Quartzite or Schist host with Quartz (SiO2) intrusion
Quartz Geode
Crystalline Silica (SiO2)
Almandine Garnet
Almandine, Fe3Al2(SiO4)3
Quartz
Silicon Dioxide (SiO2)
Ammonite fossil
Fossilized ammonoid cephalopod; likely an involute ammonite, exact genus/species indeterminate
Sandstone (likely Siltstone variety)
Arenite / Siltstone (primary mineral SiO2)
Quartz
Silicon Dioxide (SiO2)
White Quartz
Silicon Dioxide (SiO2)
Quartz (Rose Quartz or Chert variant)
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Quartz Geode with Calcite
Silicon Dioxide (SiO2) and Calcium Carbonate (CaCO3)
Chert Nodule
Microcrystalline Quartz (SiO2)
Tumbled mahogany obsidian
Volcanic glass, predominantly rhyolitic silica (SiO₂), with iron-oxide inclusions
Quartz (Tumbled)
Silicon Dioxide (SiO2)
Quartz
Silicon dioxide (SiO2)
Quartz Geode
Silicon Dioxide (SiO2) in a sedimentary host
Jasper
Microcrystalline Quartz (SiO2)