Blue Lace Agate (with Amethyst Geode center)
Silicon Dioxide (SiO2) - Cryptocrystalline Chalcedony
Category
Browse mineral (variety of chalcedony) specimens identified by the Rock Identifier community.
Blue Lace Agate (with Amethyst Geode center)
Silicon Dioxide (SiO2) - Cryptocrystalline Chalcedony
Sunstone
Oligoclase (Plagioclase Feldspar) / (Ca,Na)(Al,Si)4O8
Weathered quartz-rich pebble (tentative)
Likely quartz/chalcedony, SiO₂, possibly iron-stained
Petrified Wood
Silicified Wood (primarily SiO2)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Quartz (Milky Quartz / Quartz Crystal)
Silicon Dioxide (SiO2)
Banded Agate Geode
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Raw honey calcite (probable)
Calcite, calcium carbonate (CaCO₃)
Moss Agate
Silicon Dioxide (SiO2) with inclusions
Moss Agate
Silicon Dioxide (SiO2) with Manganese/Iron Oxide inclusions
Amethyst on Agate/Basalt Matrix
Silicon Dioxide (SiO2) with iron impurities
Carnelian
SiO2 (Silicon Dioxide with Iron Oxide impurities)
Blue Agate (Dyed)
Silicon Dioxide (SiO2) with artificial pigment
Petrified Wood
Silicified Wood (SiO2 / Quartz pseudomorph after wood)
Tumbled blue stone with a drilled hole
Likely dyed or naturally blue chalcedony/agate; identity cannot be confirmed from the photo
Red Jasper with Quartz Veining
Jasper (Silicon Dioxide, SiO2) with Quartz (SiO2) inclusions
Hematite
Hematite (Fe2O3)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz with Iron Staining
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz Geode
Silicon Dioxide (SiO2) in a sedimentary or volcanic host
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Green Fluorite
Calcium Fluoride (CaF2)
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Rose Quartz
Silicon dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Peach Moonstone
Potassium Aluminum Silicate, KAlSi3O8
Ruby (Corundum)
Aluminum Oxide (Al2O3) with Chromium traces
Rose Quartz
Silicon Dioxide (SiO2) with Titanium/Manganese/Iron trace elements
Petrified Wood
Silicified wood (primarily quartz replacing organic cellulose)
Ruby (Corundum)
Aluminum Oxide (Al₂O₃:Cr)
Yellow Aventurine
Quartzite with Muscovite/Goethite inclusions (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Lake Superior Agate
Silicon Dioxide (SiO2)
Amethyst Geode (Carved)
Amethyst (Violet Crystalline Quartz - SiO2)