Fluorite on Matrix
Calcium Fluoride (CaF2)
Category
Browse mineral specimens identified by the Rock Identifier community.
Fluorite on Matrix
Calcium Fluoride (CaF2)
Quartz geode
Microcrystalline and crystalline quartz (SiO₂), likely chalcedony-lined geode
Banded Gneiss Pebble
Gneiss (Metamorphic Rock)
Fossilized bone fragment (probable mammalian tooth or bone)
Mineralized bone, commonly hydroxyapatite [Ca5(PO4)3(OH)] replaced or impregnated by silica/calcite
Fossilized Shark Tooth
Chondrichthyes (Class)
Gneiss
Gneiss
Limonite or Goethite (Ironstone)
Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)
Kaolinite (China Clay)
Kaolinite (Al2Si2O5(OH)4)
Turquoise
CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminum)
Limonite
FeO(OH)•nH2O
Chrysocolla
Hydrated copper phyllosilicate, (Cu,Al)2H2Si2O5(OH)4·nH2O
Malachite
Copper carbonate hydroxide [Cu2CO3(OH)2]
Vesicular basalt (likely weathered lava rock)
Vesicular basalt; primarily plagioclase feldspar, pyroxene, and volcanic glass, with possible iron-oxide alteration
Snowflake Obsidian
Obsidian with Cristobalite inclusions
Tumbled or weathered gneiss
Feldspar–quartz–mica gneiss (composition variable)
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic Extrusive volcanic rock)
Blue Apatite
Calcium phosphate mineral, Ca5(PO4)3(F,Cl,OH)
Mixed Mineral Assortment (Pyrite, Kyanite, Agate, Jasper)
FeS2 (Pyrite), Al2SiO5 (Kyanite), SiO2 (Agate/Jasper)
Epidote
Epidote (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
Epidote
{Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)
Epidote
Epidote (Ca2(Al,Fe)3(SiO4)3(OH))
Epidote
Epidote ({Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH))
Limonite / Ironstone
Hydrated Iron Oxide (FeO(OH)·nH2O)
Small tumbled orange-brown mineral fragment
Indeterminate; possibly iron-stained quartz, carnelian, or orange calcite
Polished orbicular jasper (likely ocean jasper)
Silica-rich microcrystalline quartz/chalcedony with iron oxides and accessory minerals; SiO₂-dominant
Greenstone / Metabasalt
Chlorite schist or Epidiorite
Greenstone
Protolith: Basaltic rock
Greenstone
Greenschist / Meta-basalt
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Schist
Schist
Likely fluorite fragments
Fluorite (calcium fluoride, CaF₂)
Granite
Intrusive Igneous Rock (composed of quartz, alkali feldspar, and plagioclase)
Chrysocolla
Hydrated copper silicate (Cu,Al)2H2Si2O5(OH)4·nH2O
Quartz-rich pegmatite (likely mica-bearing granite)
Granitic pegmatite; chiefly quartz (SiO₂), feldspar, and mica (muscovite/biotite)
Tiger's Eye
Silicon Dioxide (SiO2) with fibrous inclusions
Sandstone
Clastic Sedimentary Rock
Note regarding baguette production (not a rock)
Digital text image - Somali language
Weathered, quartz-rich metamorphic rock (likely schist or gneiss)
Quartz–feldspar–mica schist/gneiss, with surface lichens and iron-oxide staining
Rainbow Fluorite
Fluorite (Calcium Fluoride, CaF2)
River Stones (Quartzite and Sandstone)
Quartzite / Sedimentary Rock (SiO2 dominant)
Limonite (Ironstone) pseudomorph
Limonite (Hydrous ferric oxide), FeO(OH)·nH2O
Weathered serpentinized ultramafic rock
Serpentinite; chiefly serpentine-group minerals, commonly with magnetite, brucite, talc, and relict olivine/pyroxene