Chert (Jasper/Flint variant)
Microcrystalline Quartz (SiO2)
sedimentary
Category
Organic Material (Likely A Fruit Or Berry)
Browse organic material (likely a fruit or berry) specimens identified by the Rock Identifier community.
Diopside (likely Chromian Diopside)
Diopside, part of Clinopyroxene family of inosilicates. Chemical formula: CaMgSi2O6. The green variety is often Chromian Diopside due to chromium impurities.
mineral
Iron Meteorite
Siderite (Iron-Nickel Meteorite)
mineral
Jasper (likely Lake Superior Jasper)
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary (silica-rich mineral variety)
Olivine in Basalt
Peridotite / Forsterite ((Mg,Fe)2SiO4)
igneous
Gneiss (specifically a granitic gneiss cobble)
Gneiss (high-grade regional metamorphic rock)
metamorphic
Petrified Wood
Silicified Wood (SiO2)
metamorphic
Pink Anthracite Coal (dyed)
Anthracite Coal (Artificially Colored)
Sedimentary Rock (Altered)
Horse Chestnut (Buckeye seed)
Aesculus hippocastanum seed
Organic (Non-geological)
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
sedimentary
Tourmaline (likely Schorl)
Tourmaline Group Mineral (e.g., Schorl for black varieties); (Na,Ca)(Li,Mg,Fe,Mn,Al)3Al6(BO3)3Si6O18(OH)4
Mineral
Agate (Nodule/Chert)
Silicon Dioxide (SiO2)
sedimentary
Druzy Quartz on Host Rock
Silicon Dioxide (SiO2) with various iron-oxide inclusions
mineral
Quartz Geode
Quartz (Silicon Dioxide - SiO2) within a Chalcedony and Limonite shell
sedimentary
Fossilized Coral
Scleractinian Anthozoa (Fossilized Calcium Carbonate, CaCO3)
sedimentary
Sandstone (Beach Pebble)
Clastic sedimentary rock (primarily Quartz and Feldspar)
sedimentary
Asphalt Concrete (Bituminous Pavement)
Aggregates in Bitumen Matrix
Technogenic / Anthropogenic Pavement Material
Fossiliferous Limestone (Crinoidal)
Calcium Carbonate (CaCO3) - Limestone containing bioclasts
sedimentary
Amber
Succinite (Resinous fossilized tree sap)
Mineraloid
Moss Agate
Silicon Dioxide (SiO2) with inclusions
mineral
Green Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite
sedimentary
Note: No specimen visible
N/A
Picture Jasper
Silicon Dioxide (SiO2) - Opaque Chert/Quartzite variety
sedimentary
Quartz (likely milky/rose quartz variety)
Quartz (SiO2 - Silicon Dioxide)
Mineral
Lepidolite on Pegmatite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2) in Granitic Pegmatite
igneous
Moss Agate
Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxide
mineral
Chert (Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Yellow Jasper (Mookaite style)
Silicon Dioxide (SiO2) with Goethite/Hematite inclusions
sedimentary
Gray Quartz (Tumbled)
Silicon Dioxide (SiO2)
mineral
Anthracite Coal
Anthracite (Carbon based fossil fuel)
metamorphic
Siltstone with Weathering Rind
Siltstone (composed of microscopic quartz and clay minerals)
sedimentary
Quartzite (River Cobble)
Metamorphic Rock (composed predominantly of SiO2)
metamorphic
Chert (Chalcedony/Agate)
Microcrystalline Quartz (SiO2)
sedimentary
Moss Agate
Chalcedony (SiO2) with dendritic inclusions of Manganese or Iron oxide
mineral
Sandstone (Quartzite-rich)
Clastic sedimentary rock (primarily SiO2)
sedimentary
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
metamorphic
Agatized Chert / Chalcedony
Silicon Dioxide (SiO2)
sedimentary
Sand Dollar Fossil (Echinoidea)
Class Echinoidea (likely order Clypeasteroida), CaCO3 (Calcite)
sedimentary
Olivine (Peridot)
Olivine Group (Mg,Fe)2SiO4
mineral
Sandstone
Clastic sedimentary rock (primarily SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
metamorphic