Banded Iron Formation
Banded Iron Formation (BIF)
Sedimentary
Category
Sedimentary (Secondary Classification: Cryptocrystalline Quartz)
Browse sedimentary (secondary classification: cryptocrystalline quartz) specimens identified by the Rock Identifier community.
Petrified Wood
Silicified wood (Quartz/Chalcedony replacement of organic matter)
sedimentary
Specular Hematite (Specularite)
Iron Oxide (Fe2O3)
mineral
Turquoise
Turquoise (Hydrated phosphate of copper and aluminium) CuAl6(PO4)4(OH)8·4H2O
mineral
Gold Nugget
Native Gold (Au)
mineral
Gold Nugget
Native Gold (Au)
mineral
Gold Nugget
Native Gold (Au)
mineral
Gold Nugget
Native Gold (Au)
mineral
Basalt with Amygdules
Amygdaloidal Basalt
igneous
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic volcanic rock including secondary mineral infills)
Igneous
Chert
Chert (microcrystalline quartz, SiO2)
sedimentary
Druzy Agate (Star-cut Geode Slice)
Silicon Dioxide (SiO2) - Microcrystalline and Macrocrystalline Quartz
mineral
Gold Nugget
Native Gold (Au)
mineral
Copper-bearing Quartz (with Malachite and Iron Oxides)
Quartz (SiO2) with Malachite (Cu2CO3(OH)2) and Hematite/Limonite (Fe2O3)
Mineral Specimen
Milky Quartz with Epidote or Chlorite inclusions
Silicon Dioxide (SiO2) with inclusions of Epidote {Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)
mineral
Carnelian
Chalcedony (cryptocrystalline quartz), SiO2 (Silicon Dioxide)
Mineral
Flower Agate
Chalcedony (SiO2) with Scolecite/Opaque inclusions
mineral
Copper-bearing Quartz (likely Chrysocolla or Malachite staining)
Cuprite, Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O) or Malachite staining on Quartz/Host Rock
mineral
Chrysocolla and Azurite in Matrix
Hydrated copper phyllosilicate (Chrysocolla - Cu2H2Si2O5(OH)4) and Copper carbonate (Azurite - Cu3(CO3)2(OH)2)
mineral
Green Moss Agate / Jasper
Silicon Dioxide (SiO2) - Microcrystalline Quartz with Iron and Manganese inclusions
sedimentary
Red Quartz (Ferruginous Quartz)
Silicon Dioxide with Hematite inclusions (SiO2 + Fe2O3)
mineral
Chert (often referred to as 'Jasper' when red)
Chert (microcrystalline quartz, SiO₂)
Sedimentary rock
Quartzite Pebble (with iron staining)
Quartzite (SiO2 with ferric oxide impurities)
metamorphic
Sandstone (Picture Sandstone)
Arenite (primarily SiO2)
sedimentary
Black Onyx
Silicon Dioxide (SiO2)
mineral
River Pebbles and Quartz
Mixed Igneous, Sedimentary, and Metamorphic Rocks (Silicon Dioxide SiO2 dominant)
mixed
K2 Jasper (Beads)
Granodiorite with Azurite and Malachite
igneous
Vesicular Basalt (Scoria)
Basalt (Extrusive Igneous Rock)
igneous
Vesicular Basalt
Mafic Volcanic Rock (Basalt)
igneous
Vesicular Basalt with Quartz
Vesicular Basalt (SiO2 inclusions)
igneous
Carnelian
Carnelian (a variety of Chalcedony, SiO2)
Mineral
Quartz (Smoky/Milky variant)
Silicon Dioxide (SiO2)
mineral
Citrine or Yellow Quartz
Silicon Dioxide (SiO2) with iron impurities
mineral
Chert (or possibly Flint)
Chert (variant: Flint)
Sedimentary
Quartz Pebble (Iron-Stained)
Silicon Dioxide (SiO2)
mineral
Limonite
Limonite (Hydrated iron(III) oxide-hydroxide) FeO(OH)·nH2O
mineral
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
mineral
![Turquoise with Pyrite (Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O] with Iron Pyrite (FeS2)) — mineral](https://media.rockidentification.com/157e6415-0364-437c-b0a4-74ad43800d08-thumbnail.jpg)
Turquoise with Pyrite
Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O] with Iron Pyrite (FeS2)
mineral
Calcite
Calcium Carbonate (CaCO3)
mineral
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
mineral
Chrysocolla on Limonite Matrix
Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O (Chrysocolla) on FeO(OH)·nH2O (Limonite)
mineral
Basalt
Basalt (Aphanitic mafic volcanic rock)
igneous