Pegmatitic granite, possibly potassium-feldspar-rich
Coarse-grained granite; mainly quartz (SiO₂), potassium feldspar (KAlSi₃O₈), plagioclase, and biotite/hornblende
Category
Browse mineraloid (man made glass) specimens identified by the Rock Identifier community.
Pegmatitic granite, possibly potassium-feldspar-rich
Coarse-grained granite; mainly quartz (SiO₂), potassium feldspar (KAlSi₃O₈), plagioclase, and biotite/hornblende
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Chert (often called Flint)
Chert (Microcrystalline Quartz, SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Quartz Pebble (Chalcedony/Agate)
Silicon Dioxide (SiO2)
Obsidian
Obsidian (Volcanic Glass, SiO2 + impurity isotopes)
Milky quartz
Quartz (silicon dioxide, SiO₂)
Obsidian (black volcanic glass)
Obsidian; primarily amorphous SiO₂-rich rhyolitic glass
Milky Quartz Pebble
Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Quartz Vein / Quartzite
Silicon Dioxide (SiO2)
Tumbled Quartz
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Quartz Fragment
Silicon Dioxide (SiO2)
Quartz with Mica inclusions
Silicon Dioxide (SiO2) with Muscovite/Biotite inclusions
Milky Quartz
Silicon Dioxide (SiO2)
Quartz pebble
Silicon dioxide (SiO2)
Quartz Vein in Gneiss or Schist
Silicon dioxide (SiO2) within metamorphic host rock
Milky Quartz Pebble with Hag Stone Feature
Crystalline Silicon Dioxide (SiO2)
Quartz (Raw Chunk)
Silicon Dioxide (SiO2)
Quartz (River Pebble)
Silicon Dioxide (SiO2)
Quartz Crystal Fragment
Silicon Dioxide (SiO2)
Clear Quartz
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Quartz (Milky/Smoky variety)
Silicon Dioxide (SiO2)
Quartz
Silicon dioxide (SiO2)
Quartz
Silicon dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Milky Quartz with Iron Inclusions
Silicon Dioxide (SiO2)
Quartzite
Quartzite (SiO2)
Iron-stained quartz or quartz-rich rock
Quartz (SiO₂), likely milky quartz with hematite/goethite staining
Worn quartz-rich pebble, likely chert or quartzite
Microcrystalline quartz (SiO₂), possibly quartzite
Tumbled amber-like chalcedony or resinous fossil material
Likely chalcedony (microcrystalline SiO₂), though the appearance could also indicate copal/amber
Quartzite Pebble
SiO2 (Silicon Dioxide)
Pink Quartzite
Quartzite (principally Silicon Dioxide, SiO2)
Chert (Arrowhead/Tool Grade)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)