Milky Quartz Pebble
Crystalline 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.
Milky Quartz Pebble
Crystalline Silicon Dioxide (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Chert (Jasper variety)
Silicon Dioxide (SiO2) with iron oxide impurities
Chert
Microcrystalline Quartz (SiO2)
Coquina or Fossiliferous Limestone
Fossiliferous Calcarenite (CaCO3)
Sandstone Pebble (Quartzite-rich)
Clastic Terrigenous Sedimentary Rock (SiO2 dominant)
Moss Agate
Silicon Dioxide (SiO2) with inclusions of manganese or iron oxides
Yellow Quartz (Citrine or Quartz Crystal with Iron Inclusions)
Silicon Dioxide (SiO2)
Asphalt (Road Aggregate)
Bituminous Conglomerate / Asphalt Concrete
Chert (with inclusions)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (often called Flint or River Stone)
Chert (Microcrystalline Silicon Dioxide, SiO2)
Chert (River Stone/Pebble)
Chert (SiO2)
Rough Amethyst Quartz
Silicon Dioxide with Iron impurities (SiO2)
Sandstone (Quartzose Sandstone)
Clastic sedimentary rock (SiO2 primary composition)
Chalcedony Nodule in Matrix
Silicon Dioxide (SiO2)
Agate Geode
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chalcedony (Common Opal variant or Chert/Flint)
Silicon Dioxide (SiO2)
Chinese Writing Stone
Porphyritic Basalt or Porphyritic Andesite with Feldspar phenocrysts (SiO2-rich Silicates)
Granite
Phaneritic Igneous Rock (primarily Quartz, Feldspar, and Mica)
Quartzite with Quartz Vein
Quartzite (SiO2)
Sandstone (Red Sandstone)
Clastic Sedimentary Rock (primarily SiO2 with Iron Oxide)
Moss Agate / Chalcedony
Silicon Dioxide (SiO2)
Chert (v. Flint)
Sedimentary Cryptocrystalline Quartz (SiO2)
Chert (Chert / Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chalcedony (Botryoidal or Tumbled)
Chalcedony (SiO₂)
Fossiliferous Shale
Laminated Mudrock with plant fossils
Ocean Jasper
Orbicular Jasper (variety of Chalcedony/Quartz, SiO2)
Pink Granite
Phaneritic Felsic Igneous Rock
Quartz
Silicon Dioxide (SiO2)
Milky Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Lapis Lazuli
Na8[Al6Si6O24]S2
Jasper
Jasper (Cryptocrystalline Quartz; SiO2)
Jasper
Silicon dioxide (SiO2) with impurities
Milky Quartz with Matrix
Quartz (Silicon Dioxide, SiO2)
Quartz (Milky/Smoky variety on matrix)
Silicon Dioxide (SiO2)
Vesicular Basalt with Amygdules
Amygdaloidal Basalt
Chert (River Pebble)
Microcrystalline Quartz (SiO2)
Chert (often called Flint when in chalk or limestone)
Silicon Dioxide (SiO₂)
Agate (Chert/Chalcedony)
Silicon Dioxide (SiO2)
Dendritic Agate
Chalcedony (SiO2) with manganese/iron oxide inclusions
Amygdaloidal Basalt with Epidote/Chlorite
Basalt (containing (Ca2(Al2Fe3+)(SiO4)(Si2O7)O(OH)))
Quartz (Iron-Stained)
Silicon Dioxide (SiO2)