Gemstone Ring
Various (Likely Glass, Cubic Zirconia, or assorted semi-precious stones)
gemstone
Category
Mineral Health
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Vein Quartz in Basalt or Mafic Rock
Silicon Dioxide (Quartz veins in volcanic host rock)
igneous
Concretion
Septarian Concretion
sedimentary
Banded Gneiss
Gneiss (pronounced 'nice')
metamorphic
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
mineral
Limonite (often after Pyrite)
Limonite (FeO(OH)·nH2O)
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Fossilized bone or tooth fragment
Indeterminate fossil bone; possibly mammalian or reptilian
fossil
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic Volcanic Rock)
Igneous
Granite
Granite (phaneritic felsic intrusive rock)
igneous
Schist
Mica schist, likely muscovite–biotite schist with quartz and feldspar
metamorphic
Limonite/Goethite Nodule
Iron Oxyhydroxide (primarily FeO(OH)·nH2O)
mineral
Quartz Pebbles
Silicon Dioxide (SiO2)
mineral
Limonite Nodule
FeO(OH)·nH2O (Hydrated iron oxide-hydroxide)
mineral
Sandstone
Arenite (SiO2 based with various mineral cements)
sedimentary
Sandstone with Magnetite and Iron Staining
Clastic Sedimentary Rock (contains Fe3O4 and Limonite/Hematite)
sedimentary
Chrysocolla (or Turquoise/Aventurine)
Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O
mineral
Sandstone Concretion
Clastic sedimentary rock (primarily Quartz SiO2 with mineral cement)
sedimentary
K2 stone (azurite–granite)
Biotite granite hosting blue azurite (Cu₃(CO₃)₂(OH)₂), often with malachite and quartz
igneous
Iron-stained Quartz
Silicon Dioxide (SiO2) with Iron Oxide (Limonite/Goethite) inclusions
mineral
Fossil Shark Tooth
Odontaspididae (Sand Tiger Shark family)
fossil
Quartz Veinated Sandstone or Siltstone
Silicon Dioxide (SiO2) within a clastic sedimentary matrix
sedimentary
Quartz with Limonite Staining
Silicon Dioxide (SiO2) with Hydrated Iron Oxide (FeO(OH)·nH2O)
Mineral
Vanadinite
Pb5(VO4)3Cl
mineral
Epidote
Epidote (Ca2(Al, Fe)3(SiO4)3(OH))
mineral
Polished Hematite Tower
Hematite (Fe2O3)
mineral
Stalagmite (Flowstone)
Speleothem (Calcium Carbonate, CaCO3)
sedimentary
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Quartz Geode Fragment
Silicon Dioxide (SiO2)
mineral
Azurite and Malachite on Matrix
Cu3(CO3)2(OH)2 (Azurite) and Cu2CO3(OH)2 (Malachite)
mineral
Boxwork Siderite or Sepatarian Nodule Weathering
Siderite (FeCO3) with secondary mineralization or Boxwork Geode fragment
sedimentary
Quartz vein in host rock
Quartz (SiO₂), likely in a weathered carbonate or sedimentary matrix
mineral
Vesicular basalt (scoriaceous basalt)
Basalt, primarily plagioclase, pyroxene, and iron-rich olivine; vesicular variety may be termed scoria
igneous
Limonite (Oxidized Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
mineral
Tumbled serpentine (likely bowenite/antigorite)
Serpentine-group minerals, chiefly antigorite or lizardite; commonly Mg₃Si₂O₅(OH)₄
metamorphic
Sandstone
Arenite (clastic sedimentary rock)
sedimentary
Magnetite Sand (Black Sand)
Magnetite (Fe3O4)
mineral
Quartz pebble
Silicon dioxide (SiO2)
sedimentary
Quartz Pebble
Silicon Dioxide (SiO2)
sedimentary
Bauxite
Bauxite (mixture of Hydrous Aluminum Oxides)
sedimentary
Polished mixed rock, likely orbicular/epidote-bearing granite or basalt
Uncertain; probable quartz–feldspar–amphibole/epidote aggregate
igneous
Tooth fossil, likely mammalian or reptilian fragment
Indeterminate fossilized tooth; enamel and dentine, taxon unresolved
fossil