Blue Lace Agate
Microcrystalline Quartz (Chalcedony), SiO2
Category
Browse sedimentary (secondary formation) specimens identified by the Rock Identifier community.
Blue Lace Agate
Microcrystalline Quartz (Chalcedony), SiO2
Quartz with Iron Staining
Silicon Dioxide (SiO2) with iron oxide impurities
Ferruginous Quartz (Iron-stained Quartz)
Silicon Dioxide (SiO2) with Hematite/Limonite impurities
Banded Chert (with Quartz Vein)
Microcrystalline Silica (SiO2)
Chert (with Quartz Vein)
Chert (Siliceous sedimentary rock, predominantly Microcrystalline Quartz SiO2)
Turquoise
Turquoise - CuAl6(PO4)4(OH)8·4H2O
Specular Hematite (Specularite) in Matrix
Specularite (Fe2O3)
Weathered copper-bearing rock, possibly chrysocolla-bearing quartz or host rock
Indeterminate from the photo; possible chrysocolla (hydrated copper silicate) with quartz or other host minerals
Gold Nugget
Native Gold (Au)
Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
Carnelian
Chalcedony (cryptocrystalline quartz), SiO2
Chrysocolla-bearing quartz (likely chrysocolla in quartz)
Chrysocolla, hydrated copper aluminosilicate: approximately (Cu,Al)₂H₂Si₂O₅(OH)₄·nH₂O, intergrown with quartz (SiO₂)
Quartz Crystal Cluster
Silicon Dioxide (SiO2)
Chert (Limestone-based)
Silicon Dioxide (SiO2)
Chert (Flint / Jasper)
Silicon Dioxide (SiO2)
Orange Calcite
Calcite (Calcium Carbonate, CaCO3)
Quartz crystal cluster
Quartz, silicon dioxide (SiO₂), likely milky or partially included rock crystal
Peacock Ore (Bornite or Iridescent Chalcopyrite)
Bornite (Cu5FeS4) or Chalcopyrite (CuFeS2) with oxidation
Ferruginous Quartz
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
Stichtite in Serpentine (Atlantasite)
Mg6Cr2CO3(OH)16·4H2O (Stichtite) within Mg3Si2O5(OH)4 (Serpentine)
Blue Sapphire
Corundum (Al2O3)
Conglomerate Pebble (with Chert / Quartz)
Sedimentary Conglomerate / Breccia Pebble
Limonite / Goethite Ironstone Concretion
FeO(OH)·nH2O (Hydrated Iron Oxide)
Limonite and Goethite (Ironstone)
Hydrous Iron Oxide Mixture (FeO(OH)·nH2O)
Weathered river cobble, likely basaltic or andesitic volcanic rock
Fine-grained mafic to intermediate igneous rock; exact identification requires testing
Okenite
Okenite, Ca3Si6O15·6H2O
Red Hematite (Banded Iron Formation)
Hematite (Fe2O3)
Quartz Crystal Cluster
Silicon Dioxide (SiO2)
Jasper with Purple Fluorite or Chalcedony
Silicon Dioxide (SiO2) with mineral inclusions
Likely hematite-rich iron ore
Hematite (Fe₂O₃), possibly with magnetite and/or goethite
Specular Hematite with Quartz
Ferric oxide (Fe2O3) and Silicon dioxide (SiO2)
Malachite
Cu2CO3(OH)2 (Copper carbonate hydroxide)
Quartzite Pebble (with iron staining)
Quartzite (SiO2 with ferric oxide impurities)
Celestite (Celestine)
Strontium Sulfate (SrSO4)
Agate
Silicon Dioxide (SiO2) - variety of Chalcedony
Vesicular basalt (likely weathered volcanic rock)
Basalt; primarily plagioclase feldspar, pyroxene, and sometimes olivine
Prehnite
Ca2Al(AlSi3O10)(OH)2 (Calcium Aluminum Silicate hydroxide)
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Red Jasper
Silicon dioxide (SiO2)
Banded Agate (with Quartz Geode Center)
Silicon Dioxide (SiO2)
Chert (with Quartz vein)
Chert (Silicon Dioxide, SiO2)
Gold
Gold (Native Element); Au