Banded Gneiss (with possible weathered sulfide or iron staining)
Gneiss, potentially with iron oxide/hydroxide staining (e.g., limonite) or weathered sulfides
Category
Browse sedimentary (secondary mineral) within igneous specimens identified by the Rock Identifier community.
Banded Gneiss (with possible weathered sulfide or iron staining)
Gneiss, potentially with iron oxide/hydroxide staining (e.g., limonite) or weathered sulfides
Milky Quartz
Silicon Dioxide (SiO2)
Blue Apatite
Fluoroapatite (Ca5(PO4)3F)
Yellow Calcite
Calcium Carbonate (CaCO3)
Chert (Iron-stained)
Silicon Dioxide (SiO2) with Iron Oxides
Quartz in Matrix
Silicon Dioxide (SiO2) in host rock matrix
Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Carnelian (Chalcedony)
SiO2 (Silicon Dioxide with iron oxide inclusions)
Bornite (Peacock Ore)
Cu5FeS4 (Copper Iron Sulfide)
Rhodochrosite Pebble
MnCO3 (Manganese Carbonate)
Malachite
Copper carbonate hydroxide Cu2CO3(OH)2
Prehnite
Ca2Al(AlSi3O10)(OH)2 (Calcium Aluminum Silicate)
Chrysocolla
Hydrated copper silicate (Cu,Al)2H2Si2O5(OH)4·nH2O
Prehnite
Ca2Al(AlSi3O10)(OH)2
Agate
Agate (Silicon Dioxide, SiO2)
Hematite
Iron(III) oxide (Fe2O3)
Banded Agate
Agate (Silicon Dioxide - SiO2)
Prehnite
Prehnite (Ca2Al2Si3O10(OH)2)
Bornite (Peacock Ore)
Bornite (Cu5FeS4)
Amethyst (Geode/Druzy)
Silicon Dioxide (SiO2) with iron impurities
Rainbow Moonstone
White Labradorite (var. of Anorthite), (Ca,Na)(Al,Si)4O8
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Turquoise and Red Coral
CuAl6(PO4)4(OH)8·4H2O (Turquoise) and Corallium rubrum (Red Coral)
Quartz Geode Fragment
Silicon Dioxide (SiO2)
Conglomerate
Clastic Sedimentary Rock
Cobaltian Calcite (Cobaltoan Calcite)
Cobaltian Calcite (CaCO3 with Co2+ substitution)
Quartz Geode (with Agate banding)
Silicon Dioxide (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Dalmation Stone (Dalmation Jasper)
Peralkaline rock (primarily Feldspar and Quartz with Arfvedsonite spots)
Chert (Chalcedony/Agate)
Microcrystalline Quartz (SiO2)
Quartz Geode (Amethyst / Clear Quartz)
Silicon Dioxide (SiO2)
Botryoidal Chalcedony
Silicon Dioxide (SiO2)
Ironstone Concretion / Limonite-stained Siltstone
Ironstone (primarily Limonite FeO(OH)·nH2O and Siltstone)
Porphyry
Porphyritic Andesite / Basaltic Porphyry
Agate
Silicon Dioxide (Chalcedony), SiO2
Chalcopyrite in River Pebble (Pebble with Pyrite/Fool's Gold inclusions)
CuFeS2 in fine-grained igneous host rock (Basalt / Andesite)
Quartz (Milky/Clear variety)
Silicon Dioxide (SiO2)
Magnetite (Lodestone)
Magnetite (Fe3O4)
Ironstone Nodule
Ferruginous Sandstone / Limonite Concretion
Amethyst
Silicon dioxide with iron impurities (SiO2:Fe3+)
Pebble with Basaltic and Quartz-rich Banding
Polymictic Lithic Pebble