Iceland Spar (Optical Calcite)
Calcite (CaCO3)
Category
Browse sedimentary or igneous specimens identified by the Rock Identifier community.
Iceland Spar (Optical Calcite)
Calcite (CaCO3)
Agate
Silicon dioxide (chalcedony), SiO2
Quartz
Silicon Dioxide (SiO2)
Pyrite
Iron Sulfide (FeS2)
Carnelian
Carnelian (SiO2)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Quartz (Milky/Crystalline fragment)
Silicon Dioxide (SiO2)
Pyrite and Sunstone
Iron Sulfide (FeS2) and Plagioclase Feldspar ((Ca,Na)Al(Al,Si)Si2O8)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Yellow Calcite
Calcium Carbonate (CaCO3)
Quartz vein in host rock
Quartz (SiO₂), likely milky quartz; host rock is uncertain from the photo
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
White Quartz (Milky Quartz)
Quartz (Silicon Dioxide - SiO2)
Quartz on Matrix
Silicon Dioxide (SiO2)
Quartz pebble
Silicon dioxide (SiO2)
Dalmatian Stone (commonly Dyed)
Dalmatian Jasper (Peralkaline igneous rock)
Orbicular rhyolite (likely)
Silica-rich volcanic rock, chiefly quartz and feldspar with orbicular aggregates of feldspar, quartz, and mafic minerals
Dalmatian Jasper
Peralkalic Quartz-Feldspar Porphyry
Dalmatian Stone
Peralkaline rhyolite
Weathered limestone or calcareous sandstone
Calcitic carbonate rock, likely limestone (CaCO₃), possibly slightly dolomitic
Dalmatian Stone (often misnamed Dalmatian Jasper)
Aplite (with hornblende/arfvedsonite inclusions)
Silicified oyster fossil
Fossil oyster shell, commonly Ostrea or Crassostrea, replaced or encrusted by chalcedony/quartz
Quartz
SiO2 (Silicon Dioxide)
Quartz
Silicon dioxide (SiO2)
Quartz and Unakite
SiO2 (Quartz) / Epidote, Pink Orthoclase, Quartz (Unakite)
Quartz pebble with iron staining
Silicon dioxide (SiO2) with iron oxide impurities
Carnelian Agate
Silicon Dioxide (SiO2) with iron oxide inclusions
Grey Banded Agate
Silicon Dioxide (SiO2)
Magnetite or Hematite Nodule
Iron Oxide (Fe3O4 or Fe2O3)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Milky Quartz
Silicon Dioxide (SiO2)
Massive White Quartz
Silicon Dioxide (SiO2)
Epidote with Quartz Vein
Epidote-bearing metamorphic rock with quartz (Ca2(Al,Fe)3(SiO4)3(OH))
Yellow Quartz
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Orange Quartz / Peach Aventurine
Silicon Dioxide (SiO2)
Magnetite / Lodestone
Magnetite (Fe3O4)
Pyrite
Iron Sulfide (FeS2)
Magnetite / Hematite mix
Magnetite (Fe3O4) and Hematite (Fe2O3)
Orange Calcite
Calcium Carbonate (CaCO3)
White Quartz
Silicon Dioxide (SiO2)