Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Category
Browse the purple specimen is a mineral (amethyst); the white specimen is a sedimentary rock (limestone or marble). specimens identified by the Rock Identifier community.
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Quartz Pebble (Chert/Chalcedony)
Silicon Dioxide (SiO2)
Asphalt Concrete (Bituminous Conglomerate)
Anthropogenic Bituminous Conglomerate
Yellow Quartz (Citrine or Quartzite Pebble)
Silicon Dioxide (SiO2)
Amethyst
Amethyst (Silicon Dioxide - SiO2 with Iron impurities)
Basalt with Secondary Mineralization (Likely Zeolites or Calcite)
Aphanitic mafic volcanic rock with secondary mineral inclusions (e.g., CaAl2Si3O10·3H2O for Scolecite)
Quartzite Pebble
Quartzite (predominantly Silicon Dioxide - SiO2)
Blue Calcite
Calcium Carbonate (CaCO3)
Quartz vein in metamorphic rock
Crystalline Silicon Dioxide (SiO2) in Host Rock
Boxwork Siderite or Sepatarian Nodule Weathering
Siderite (FeCO3) with secondary mineralization or Boxwork Geode fragment
Chert (Jasper-rich)
Microcrystalline/Cryptocrystalline Quartz (SiO2)
Milk Quartz (with Iron staining)
Silicon Dioxide (SiO2)
Chert (or Flint)
Chert (a cryptocrystalline variety of quartz, SiO2)
Banded Sandstone
Arenite with Liesegang banding (primarily SiO2 with FeO(OH) impurities)
Turquoise
Hydrated phosphate of copper and aluminum, CuAl6(PO4)4(OH)8·4H2O
Milky Quartz
Silicon Dioxide (SiO2)
Black River Stone (likely Basalt or Chert)
Basalt (primarily Plagioclase Feldspar and Pyroxene)
Massive Cryptocrystalline Quartz (Chert/Chalcedony Pebble)
Silicon Dioxide (SiO2)
Unable to Identify (Image Obscured)
Jasper
Silicon dioxide (SiO2) with iron oxide inclusions
Corundum (Sapphire/Ruby in Matrix)
Corundum (Al2O3)
Sandstone (Yellow/Tan)
Clastic sedimentary rock (primarily SiO2 with iron oxide staining)
Desert Rose
Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O
Smoky Quartz and Chalcedony Geode Fragment
Silicon Dioxide (SiO2)
Quartzite (River Pebble)
Metamorphosed Quartz Sandstone (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Quartzite
Quartzite (composed primarily of SiO2)
Breciated Limestone with Calcite Veins
Sedimentary Breccia (CaCO3)
Slate with Quartz Vein
Foliated Metamorphic Rock (Mainly Quartz, Muscovite, Chlorite)
Rough Citrine Quartz
Silicon Dioxide (SiO2) with iron impurities
Chert (specifically Red Chert / Jasper nodule)
Silicon dioxide (SiO2)
Fluorite (left), Sodalite (middle), Dumortierite/Tumbled Quartzite (right)
Calcium Fluoride (CaF2), Sodium Aluminum Silicate Chloride (Na8(Al6Si6O24)Cl2), Aluminum Borosilicate (Al7(BO3)(SiO4)3O3)
Sandstone
Arenite (predominantly SiO2)
Milky Quartz (or Iron-Stained Quartz)
Quartz (Silicon Dioxide, SiO2)
Sand Dollar Fossil
Echinoidea (Clypeasteroida)
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily Quartz with Limonite/Goethite staining)
Sandstone
Arenite (SiO2 based with quartz grains)
Quartzite pebble
Quartzite (SiO2)
Biotite Schist with Garnet
Garnet-Biotite Schist
Quartz Pebble (with Mica or Iron staining)
Silicon Dioxide (SiO2)
Chert (Flint)
Chert (Silicon Dioxide, SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)