Red Sandstone
Arenite (Ferruginous Sandstone)
sedimentary
Category
Anthropogenic (Man Made Material Processed By Nature)
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Quartz
Silicon Dioxide (SiO2)
mineral
Olivine (Peridotite)
(Mg,Fe)2SiO4 (Magnesium Iron Silicate)
igneous
Weathered iron-rich concretion (probable limonite/goethite)
Limonite–goethite aggregate, approximately FeO(OH)·nH₂O
mineral
Emerald
Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities
mineral
Ferruginous Sandstone
Clastic Sedimentary Rock (Sandstone with Iron Oxide cement)
sedimentary
Amygdaloidal Basalt
Amygdaloidal Basalt with Secondary Mineral Amygdules
igneous
Quartz Vein in Host Rock
Silicon Dioxide (SiO2)
mineral
Aquamarine with Quartz
Beryl (Be3Al2Si6O18) with Quartz (SiO2)
mineral
Quartz Vein in Host Rock (Gabbro or Basalt)
Silicon Dioxide (SiO2) with Mafic Silicates
metamorphic/igneous
Hematite (Iron Ore)
Hematite (Fe2O3)
mineral
Olivine (Peridot)
Magnesium Iron Silicate (Mg,Fe)2SiO4
Mineral
Agate (Nodule/Chert)
Silicon Dioxide (SiO2)
sedimentary
Weathered metallic-looking rock, possibly hematite-bearing ironstone
Hematite-rich ironstone; hematite Fe₂O₃, potentially with magnetite Fe₃O₄ and quartz
mineral
Citrine
Silicon Dioxide (SiO2) with iron impurities
gemstone
Chert (Quartz)
Silicon Dioxide (SiO2)
sedimentary
Diamond (Cut and Polished)
Diamond (pure Carbon, C)
gemstone
Diamond
Carbon (C)
mineral
Rough Sapphire (Corundum)
Corundum (Al2O3)
mineral
Peridot (Olivine)
Olivine, (Mg, Fe)2SiO4
mineral
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Quartzite Pebble
Quartzite (SiO2)
metamorphic
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Granite (Dioritic variant)
Granite (Phaneritic Igneous Rock)
igneous
Chert
Chert (Microcrystalline Quartz, SiO2)
sedimentary
Biotite-bearing granite or granitic gneiss
Quartz–feldspar–biotite assemblage; possibly metamorphosed granite (gneiss)
igneous
Natural Pearl
Calcium carbonate (primarily Aragonite and Conchiolin), CaCO3
mineral
Fluorite
Calcium fluoride (CaF2)
mineral
Sandstone
Arenite
sedimentary
Flint / Chert
Silicon dioxide (Microcrystalline quartz, SiO2)
sedimentary
Sandstone
Arenite (SiO2 composed primarily of quartz)
sedimentary
![Turquoise (Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]) — Mineral](https://media.rockidentification.com/2fc8ee47-9aaf-4e01-9b51-63927847540c-thumbnail.jpg)
Turquoise
Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]
Mineral
Red Scoria (Lava Rock)
Vesicular Basalt / Scoria
igneous
Sandstone
Arenite (SiO2 principal)
sedimentary
Olivine (Peridot when gem-quality)
Magnesium Iron Silicate (Mg,Fe)2SiO4
mineral
Yellow Ochre / Limonite
Limonite (inter-mixed iron oxides and hydroxides, primarily FeO(OH)·nH2O)
mineral
Olivine (Peridotite)
(Mg,Fe)2SiO4 (Magnesium Iron Silicate)
igneous
Olivine (Peridot)
(Mg,Fe)2SiO4
mineral
Tumbled sandstone pebble
Quartz-rich sandstone, commonly subarkose or arkose
sedimentary
Weathered brown mineralized rock
Likely iron-stained quartzite or quartz-rich metamorphic rock; exact identification requires testing
metamorphic
Weathered granite or granitic gneiss
Granite; chiefly quartz, feldspar, and mica (possibly gneissic if foliation is confirmed)
igneous
Green copper-mineral specimen, likely chrysocolla or copper-bearing serpentine
Tentatively chrysocolla (hydrated copper phyllosilicate, approximately (Cu,Al)2H2Si2O5(OH)4·nH2O); exact identification requires testing
mineral