Small weathered mineral/rock fragment
Indeterminate; possibly quartz-bearing feldspathic rock or calcite-rich specimen
Category
Browse mixed: igneous and sedimentary specimens identified by the Rock Identifier community.
Small weathered mineral/rock fragment
Indeterminate; possibly quartz-bearing feldspathic rock or calcite-rich specimen
Magnetite (Iron Ore)
Iron(II,III) oxide (Fe3O4)
Quartz
Silicon Dioxide (SiO2)
Pyrite
Iron Sulfide (FeS2)
Orange Calcite
Calcium Carbonate (CaCO3)
Green Opal
Hydrated Silica (SiO2·nH2O)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Quartz-rich pebble
Mostly quartz (SiO₂), possibly a quartzite or vein-quartz fragment
Quartz (Raw Chunk)
Silicon Dioxide (SiO2)
Pyrite (Fools Gold)
Iron Disulfide (FeS2)
Geode (Unopened)
Quartz/Chalcedony concretion
Feldspar
KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8 (Feldspar group)
Carnelian / Agate
Silicon Dioxide (SiO2) - Chalcedony
Unidentified Dark Mineral or Rock
Indeterminate (Likely Silicon Dioxide or Carbon-based)
Quartz
Silicon Dioxide (SiO2)
Pyrite
Iron Pyrite (FeS2)
Quartz (Iron-stained Quartz)
Silicon Dioxide (SiO2)
Quartz Crystal
Silicon Dioxide (SiO2)
Galena
Lead Sulfide (PbS)
Quartz Pebble
Silicon Dioxide (SiO2)
Quartz (Agate/Jasper pebble)
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Quartz (Milky/Snow)
Silicon Dioxide (SiO2)
Blue Apatite
Fluoroapatite (Ca5(PO4)3F)
Hematite
Iron(III) oxide (Fe2O3)
Biotite (Black Mica)
Biotite - K(Mg,Fe)3(AlSi3O10)(F,OH)2
Pyrite
Iron Sulfide (FeS2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Likely rough quartz with iron-oxide staining
Quartz (SiO₂), possibly with iron-oxide inclusions or surface staining
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Quartz (Smoky/Milky variety)
Silicon Dioxide (SiO2)
Druzy Quartz
Silicon Dioxide (SiO2)
Botryoidal Chalcedony
Chalcedony (SiO2)
Magnetite (Iron Ore)
Magnetite (Fe3O4)
Dalmatian Stone (often called Dalmatian Jasper)
Peralkaline Feldsphathic Igneous Rock
Quartz Crystal
Silicon Dioxide (SiO2)
Magnetite / Ironstone
Iron(II,III) oxide (Fe3O4)
Magnetite (Iron Ore)
Magnetite (Fe3O4)
Quartz (Milky/Clear variety)
Silicon Dioxide (SiO2)
Magnetite / Hematite mix (Iron Ore)
Fe3O4 (Magnetite) / Fe2O3 (Hematite)
Magnetite
Magnetite (Fe3O4)