Limonite (often after Pyrite)
Limonite (FeO(OH)·nH2O)
mineral
Category
Organic Materia (Not A Rock Or Mineral)
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Granite
Intrusive igneous rock
igneous
Granite and Porphyry Pebbles
Intrusive Igneous Rock
igneous
Sandstone Concretion (Omar or Nut Rock)
Sedimentary Concretion (specifically an 'Omarolluk' or Omar)
sedimentary
Amygdaloidal Basalt with Epidote/Chlorite
Basalt (containing (Ca2(Al2Fe3+)(SiO4)(Si2O7)O(OH)))
igneous
Flint (chert), likely brown flint
Microcrystalline quartz/chalcedony (SiO₂)
sedimentary
Amethyst, Aquamarine, and Pearl Ring
SiO2 (Amethyst), Be3Al2Si6O18 (Aquamarine), CaCO3 (Pearl)
gemstone
Graphite
Graphite (C)
mineral
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
sedimentary
Red Sandstone (with possible iron oxide staining)
Sandstone (primarily Quartz with Hematite/Goethite cement)
sedimentary
Quartz with inclusions (likely Chlorite or Hornblende) and country rock
SiO2 (Quartz) with associated ferromagnesian minerals
Mineral/Igneous/Metamorphic association
Copper Ore Bearing Rock
Host rock with secondary copper minerals (such as Malachite, Azurite, and Chrysocolla)
mineral
Glauconite (Greensand)
Glauconite (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2
sedimentary
Sandstone
Clastic Sedimentary Rock
sedimentary
Botryoidal chalcedony (possibly agate/geode material)
Microcrystalline quartz, SiO₂; commonly chalcedony with quartz-lined cavities and iron-oxide staining
mineral
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Fossil Coral (Favosites Honeycomb)
Favosites (Genus), Phylum Cnidaria, Class Anthozoa
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Fossiliferous Sandstone (with Brachiopod or Bivalve mold)
Clastic Sedimentary Rock with Macrofossil Mold
sedimentary
Chalcopyrite
Copper iron sulfide (CuFeS2)
mineral
Green Jasper
Silicon Dioxide (SiO2)
sedimentary
Granite
Granite (Phaneritic intrusive igneous rock)
igneous
Dyed Dalmatian Stone
Aplite (Alkali-feldspar granite) with Arfvedsonite
igneous
Biotite (Black Mica)
Biotite - K(Mg,Fe)3(AlSi3O10)(F,OH)2
mineral
Sandstone
Arenite
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Turquoise
CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminium)
mineral
Sandstone
Arenite (SiO2 primarily)
sedimentary
Granite
Felsic intrusive igneous rock
igneous
Variscite (or potentially a turquoise/variscite matrix cabochon, or an impression jasper)
AlPO4·2H2O (Variscite) or related phosphate/silicate material depending on exact composition
Mineral
Azurite and Malachite on Matrix
Cu3(CO3)2(OH)2 (Azurite) and Cu2CO3(OH)2 (Malachite)
mineral
Granite or Pegmatite in host rock
Granitoid / Felsic Intrusive Rock
Igneous
Granite
Phaneritic Felsic Igneous Rock
igneous
Jasper and Chalcedony
Silicon Dioxide (SiO2) microcrystalline quartz
sedimentary
Breccia
Sedimentary Breccia
sedimentary
Sandstone
Sedimentary Rock (Quartz arenite or arkose)
sedimentary
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) within Metasedimentary or Igneous Matrix
metamorphic
Greenschist
Greenschist facies rock
Metamorphic
Granite with Pyrite or Mica
Phaneritic intrusive igneous rock
igneous
Basalt with Quartz Veining
Veined Basalt (composed primarily of plagioclase feldspar, pyroxene, and olivine with quartz/calcite infill)
igneous
Quartz Vein / Quartz Matrix
Silicon Dioxide (SiO2)
mineral
Porphyritic Basalt (with Pyrolusite or Iron-oxide staining)
Porphyritic Basalt (Mafic Extrusive)
igneous