Sandstone (specifically Cross-bedded Sandstone)
Arenite (composed primarily of SiO2)
Category
Browse mineral (specifically, a variety of the mineral species pyrope almandine garnet) specimens identified by the Rock Identifier community.
Sandstone (specifically Cross-bedded Sandstone)
Arenite (composed primarily of SiO2)
Sandstone (likely Siltstone)
Arenite or Siltstone (high SiO2 content)
Jasper
Jasper (Silicon Dioxide, SiO2)
Opalite
Synthetic Opalite Glass (Silicon Dioxide)
Green Fluorite
Fluorite (Calcium Fluoride, CaF2)
Agate
Silicon Dioxide (SiO2) - Variety of Chalcedony
Blue Quartz (Blue Aventurine)
Silicon Dioxide (SiO2) with inclusions (typically crocidolite or dumortierite)
Orthoclase Feldspar
Potassium Aluminum Silicate (KAlSi3O8)
Peridot (likely, given the color and bead form)
Olivine, variety Peridot (Mg,Fe)2SiO4
Magnetite (Lodestone variety)
Magnetite (Fe3O4)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz with Iron Inclusions
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz (Milky or Cloudy Quartz)
Silicon Dioxide (SiO2)
Quartz Geode
Silicon Dioxide (SiO₂)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz (Tumbled)
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions
Gneiss (specifically a Banded Gneiss cobble)
Gneiss (composed mainly of Quartz, Feldspar, and Biotite/Amphibole)
Citrine Quartz
SiO2 (Silicon Dioxide with Iron impurities)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz
Quartz (SiO₂)
Quartz (milky variety)
SiO2 (Silicon Dioxide)
Dendritic Agate
Silicon Dioxide (SiO2) with inclusions
Desert Rose
Gypsum (variety Selenite) or Barite, CaSO4·2H2O
Amazonite
Amazonite (KAlSi3O8, a triclinic variety of Potassium Feldspar)
Citrine Quartz
Silicon Dioxide (SiO2) with iron impurities
Milky Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Rose Quartz
Quartz (SiO₂), variety Rose Quartz
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
Quartz
Silicon Dioxide (SiO2)
Amethyst
SiO2 (Silicon Dioxide)
Jasper
Silicon dioxide (SiO2)
Beryl (likely Aquamarine or Green Beryl)
Beryllium aluminum silicate (Be3Al2Si6O18)
Gneiss (specifically Granitic Gneiss)
Gneissic Metamorphic Rock
Chert (specifically Banded Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Granite (specifically Rapakivi Granite)
Phaneritic Felsic Igneous Rock (Granite)
Chert (specifically Banded Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)