Granite
Granite (Mainly Quartz, Alkali Feldspar, and Plagioclase)
Category
Browse mineral, often found as a rock (metamorphic) specimens identified by the Rock Identifier community.
Granite
Granite (Mainly Quartz, Alkali Feldspar, and Plagioclase)
Sandstone
Arenite (primarily SiO2)
Sandstone (Wonderstone)
Arenite (composed primarily of SiO2 with Fe2O3 impurities)
Aventurine
Silicon Dioxide (SiO2) with inclusions
Chalcopyrite
Copper Iron Sulfide (CuFeS2)
Pyrite
Iron Sulfide (FeS2)
Sandstone
Arenite (Siliclastic sedimentary rock)
Slate
Foliated Metamorphic Rock (primarily clay minerals and micas)
Sandstone
Arenite (composed primarily of SiO2)
Quartz
Quartz (SiO₂ - Silicon Dioxide)
Amygdaloidal Basalt
Amygdaloidal Basalt containing Zeolite or Quartz (SiO2/Silicates)
Druzy Quartz on Host Rock
Silicon Dioxide (SiO2)
Galena
Lead(II) sulfide (PbS)
Geode with Quartz Crystal Cavity
Silicon Dioxide (SiO2) in Calcareous/Siliceous Matrix
Quartz Vein (Iron-stained)
Silicon Dioxide (SiO2) with limonite/hematite staining
Aventurine (Tan/Cream colored)
Quartz (SiO2) with mineral inclusions
Shale
Fissile Siliciclastic Sedimentary Rock
Epidosite (Epidote-rich rock)
Epidotalite (primarily Ca2(Al2Fe3+)(SiO4)(Si2O7)O(OH))
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Green Aventurine (likely)
Silicon dioxide (SiO2) with fuchsitemica inclusions
Shale
Fissile Mudstone (primarily composed of phyllosilicate minerals like kaolinite, montmorillonite, and illite)
Glauconite (Green Sandstone)
Glauconite (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2
Orange Calcite
Calcite (Calcium Carbonate, CaCO3)
Black Sapphire
Corundum (Al2O3 with inclusions of hematite or ilmenite)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Rough Citrine Quartz
Silicon Dioxide (SiO2) with iron impurities
Biotite (Mica)
K(Mg,Fe)3AlSi3O10(OH,F)2
Sodalite
Sodalite (Na8Al6Si6O24Cl2)
Hematite
Iron(III) oxide (Fe2O3)
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
Lapis Lazuli
Na8[Al6Si6O24]n(S,Cl,SO4,OH)2
Pet Rock (Man-made Quartzite or Granite Cobble)
Silicon dioxide (SiO2) mixture; commonly composed of Quartz, Feldspar, and Mica
Gneiss
Gneiss
Gneiss (Banded Gneiss)
Gneiss
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Fuchsite with Ruby
Cr-rich Muscovite with Corundum (K(Al,Cr)2(AlSi3O10)(OH)2)
Red Sandstone
Sandstone (principally Quartz with Iron Oxide coating)
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
Smoky Quartz
Smoky Quartz (Silicon Dioxide, SiO2)
Quartz (Small Fragment)
Silicon Dioxide (SiO2)
Fossilized Bone Fragment
Permineralized Vertebrate Fossil (Hydroxyapatite replaced by Minerals)