Carnelian Agate
Silicon Dioxide (SiO2)
Category
Browse mineral, specifically a cryptocrystalline quartz variety specimens identified by the Rock Identifier community.
Carnelian Agate
Silicon Dioxide (SiO2)
Ruby
Corundum (Al2O3 with Chromium impurities)
Chalcedony Pebble / Rough Agate
Silicon Dioxide (SiO2)
Granodiorite
Granodiorite (Intermediate to Felsic Intrusive Rock)
Agate (specifically, multi-colored or pastel-dyed agate)
Silicon dioxide (SiO2) - specifically, a cryptocrystalline variety of quartz known as Chalcedony, with banding classified as Agate. (If it were Fluorite, the chemical formula would be Calcium Fluoride - CaF2).
Chert (specifically Black Chert or Flint)
Cryptocrystalline Quartz (SiO2)
Chert (specifically a Chert Nodule or Flint)
Cryptocrystalline Quartz (SiO2)
Feldspar (specifically Orthoclase)
Potassium aluminum silicate (KAlSi3O8)
Chalcedony (specifically Agate or Flint)
Silicon Dioxide (SiO₂)
Chert (specifically Flint or Jasper variant)
Microcrystalline quartz (SiO2)
Jasper (specifically Yellow/Red Jasper)
Silicon Dioxide (SiO2) with iron oxide inclusions
Amazonite
Microcline (variety Amazonite), K(AlSi3O8)
Fuchsite
Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)
Chalcedony (Agate / Jasper Specimen)
Silicon Dioxide (SiO2)
Likely polished/tumbled quartz-rich specimen
Quartz, silicon dioxide (SiO₂), possibly an agate or chalcedony variety
Red/orange chalcedony (carnelian), possibly dyed or heat-treated
Chalcedony, cryptocrystalline SiO₂ (quartz variety)
Lake Superior Agate
Agate (Cryptocrystalline variety of Quartz, SiO2)
Carnelian Agate
Silicon Dioxide (SiO2)
Blue Agate Geode (Dyed)
Cryptocrystalline Quartz (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Banded Agate (Onyx variety)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Red Jasper
Microcrystalline Quartz (Chalcedony), SiO2 with iron oxide inclusions
Red Quartzite
Quartzite (mostly SiO2)
Red Jasper with Quartz Veining
Silicon Dioxide (SiO2) - Microcrystalline Quartz with Iron Oxide impurities (Hematite)
Desert Rose
Gypsum (variety Selenite) or Baryte, CaSO4 · 2H2O
Porphyry
Porphyritic Rhyolite or Andesite
Epidote (Unakite variety)
Epidosite (Metasomatic rock containing Ca2(Al,Fe)3(SiO4)3(OH))
Chert (specifically Jasper/Flint pebble)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Red Jasper with Hematite
Impure Microcrystalline Quartz (SiO2) with Hematite (Fe2O3)
Ruby in Fuchsite
Corundum (Al2O3) in Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2)
Chalcedony with Quartz
Silicon Dioxide (SiO2)
Likely tumbled jasper or iron-rich chert
Microcrystalline quartz (SiO₂), possibly colored by iron oxides
Chert (specifically Blue Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (specifically Gray/Blue Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Fossil Coral
Hexagonaria or Rugose Coral (petoskey stone / fossilized rugose or tabulate coral)
Amazonite
Amazonite (KAlSi3O8)
Red Jasper
Jasper (Silica with Hematite impurities), SiO2
Chalcedony Bangle
SiO2
Peach Moonstone
Orthoclase Feldspar (KAlSi3O8)
White Jade (Nephrite)
Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)
Agate
Agate (Cryptocrystalline variety of Quartz, SiO2)
Chert Pebble with Quartz Veins
Microcrystalline Quartz (SiO2)