Banded Chert (River Pebble)
Microcrystalline Quartz (SiO2)
Category
Browse organic material (likely a fruit or berry) specimens identified by the Rock Identifier community.
Banded Chert (River Pebble)
Microcrystalline Quartz (SiO2)
Chert (Mudstone)
Microcrystalline Quartz (SiO2)
Quartzite Pebble
Quartzite (primarily SiO2)
Amygdaloidal Rhyolite (often called Lake Superior Agate relative)
Rhyolite with Calcite/Quartz amygdules (SiO2 and secondary minerals)
Basalt River Cobble
Basalt (Aphanitic Mafic Volcanic Rock)
Andesite Porphyry
Andesite (extrusive volcanic rock)
Tree Agate (also known as Dendritic Agate)
Silicon Dioxide with inclusions (SiO2 + Mn/Fe)
Amber
Succinite (fossilized tree resin)
Human Skin (Epidermis/Dermis)
Integumentary tissue (High content of hydroxyapatite in bones, though the surface is biological)
Orange Quartzite / River Pebble
Quartzite (primarily SiO2)
Granite (Alkali-feldspar rich)
Phaneritic Felsic Igneous Rock (Major components: KAlSi3O8, SiO2)
Milky Quartz with Iron Staining
Quartz (Silicon Dioxide) - SiO2
Botryoidal Black Chalcedony Geode (Black Grape Agate)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Granite
Phaneritic plutonic felsic igneous rock
Granite
Phaneritic Plutonic Felsic Rock
Quartz Pebble
Silicon Dioxide (SiO2)
Jasper with Quartz Druzy
Silicon Dioxide (SiO2)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Quartz Pebble
Silicon Dioxide (SiO2)
Porphyritic Andesite
Andesite (Porphyry)
Quartz Crystal with Inclusions
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Quartzite Pebble
Metamorphosed Quartz Sandstone (SiO2)
Yellow Chert (Gold-colored River Pebble)
Microcrystalline Quartz (SiO2) with Limonite/Goethite staining
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Sandstone (specifically Flagstone)
Arenite (primarily composed of SiO2)
Quartz (Milky/Clear variety)
Silicon Dioxide (SiO2)
Jasper (Green Jasper/Chert)
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Banded Agate (with small Geode cavity)
Silicon Dioxide (SiO2) - Chalcedony variety
Gneiss (specifically Pink Gneiss)
Gneiss (high-grade regional metamorphic rock)
Clear/White Quartz (Rock Crystal)
Quartz (Silicon Dioxide, SiO2)
Agate (specifically a Blue Agate Geode Slice)
Chalcedony (cryptocrystalline variety of Quartz); SiO2
Shungite
Shungite (carbon-rich Precambrian rock)
Fossilized Crab Carapace (Concretion)
Decapoda (fossil), typically preserved in calcite or siderite concretion
Clear Quartz
Silicon Dioxide (SiO2)
André Landed Here Rock (Glacial Erratic)
Granodiorite / Diorite (compositional estimate)
Amazonite
Amazonite (KAlSi3O8)
Amber
Succinite (C10H16O)
Gneiss (specifically a Granitic Gneiss)
Gneiss (typically composed of Quartz, Feldspar, and Mica/Amphiboles)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)