Rough Quartz (or Quartzite pebble)
Silicon Dioxide (SiO2)
Category
Browse mineral within a sedimentary rock specimens identified by the Rock Identifier community.
Rough Quartz (or Quartzite pebble)
Silicon Dioxide (SiO2)
Hag Stone
Calcareous sedimentary rock (often Chert, Flint, or Limestone)
Amethyst
Crystalline Silicon Dioxide with Iron impurities (SiO2)
Dendritic Agate (specifically Orange/Tumbled)
Silicon Dioxide (SiO2) with Oxide Inclusions
Granite (Dioritic variant)
Granite (Phaneritic Igneous Rock)
Petrified Wood
Silicified Wood (primarily SiO2)
Amethyst (Polished Cabochon)
Silicon Dioxide (SiO2) with iron impurities
River Siltstone Pebble
Siltstone (primarily composed of silica and clay minerals)
Gneiss
Gneiss (High-grade metamorphic rock)
Smoky Quartz
Smoky Quartz (SiO ₂)
Agatized Chert / Chalcedony
Silicon Dioxide (SiO2)
Bumblebee Jasper
Calcite-Auripigment-Pyrite-Realgar assemblage (Carbonate/Sulphide mixture)
Granite
Granite
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Banded Gneiss
Gneiss (High-grade regional metamorphic rock)
Gneiss
Gneiss
Ironstone Nodule (Ironstone Concretion)
Siderite-rich Mudstone (FeCO3) or Limonite (FeO(OH)·nH2O)
Greywacke with Quartz Veins
Lithic Sandstone (Greywacke) with SiO2 inclusions
Quartz (Milky or Cloudy Quartz)
Silicon Dioxide (SiO2)
Banded Agate (Onyx variety)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Blue Calcite
Calcium Carbonate (CaCO3)
Carnelian (a variety of Chalcedony)
Cryptocrystalline Quartz (SiO2) with iron oxide inclusions
Blue Chalcedony
Silicon Dioxide (SiO2)
Druzy Quartz on Agate/Chert
Silicon Dioxide (SiO2)
Greywacke (River Slikkenstone)
Greywacke (Impure Sandstone)
Granite with Biotite and Quartz
Phaneritic Felsic Igneous Rock (composed of SiO2, KAlSi3O8, and K(Mg,Fe)3AlSi3O10(OH)2)
Agate (specifically Waterline or Onyx-type Agate)
Silicon Dioxide (SiO2) - variety Chalcedony
Jasper with Quartz inclusion
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Diamond
Diamond (C)
Green Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite
Petrified Wood
Silicified Wood (primarily Chalcedony or Quartz, SiO2)
Dendritic Opal (Common Opal)
Amorphous Hydrated Silica (SiO2·nH2O) with Manganese or Iron Oxide inclusions
Sandstone (Red)
Arenite (primarily Quartz, SiO2, with Iron Oxide cement)
Red Sandstone
Arenite (Ferruginous Sandstone)
Dark Igneous Rock (Likely Basalt or Diabase)
Basalt (extrusive igneous rock) or Diabase (intrusive igneous rock - also known as Dolerite), largely composed of plagioclase feldspar, pyroxene (augite), and sometimes olivine and amphibole. Exact mineralogy would require thin section analysis.
Banded Gneiss
Gneiss (High-grade Metamorphic Rock)
Chert (Nodule)
Microcrystalline or Cryptocrystalline Silica (SiO2)
Sandstone (with Liesegang rings or joints)
Clastic Sedimentary Rock (primarily Quartz with Iron Oxide cement)
Mica Schist
Foliated Metamorphic Rock (rich in Muscovite or Biotite)
Chert (Brecciated or Veined)
Silicon Dioxide (SiO2)
Apache Tear
Obsidian (Hydrated Volcanic Glass) - SiO2 (with impurities)
Granitic Gneiss
Gneiss (High-grade Metamorphic Rock)