Red Sandstone
Arenite (SiO2 with Fe2O3)
sedimentary
Category
Man Made Material, Not A Natural Rock Or Mineral Specimen
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Diamond
Carbon (C)
mineral
Yellow Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Granite
Phaneritic Plutonic Felsic Rock
igneous
Red Jasper
Silicon Dioxide (SiO2) with Hematite (Fe2O3)
sedimentary
Chert (Yellow Jasper variant)
Silicon Dioxide (SiO2)
sedimentary
Snowflake Obsidian
Volcanic Glass (SiO2 with Cristobalite inclusions)
igneous
Blue chalcedony (likely dyed or polished)
Chalcedony, microcrystalline quartz (SiO₂)
mineral
Green Quartz (Prasiolite/Adventurine)
Silicon Dioxide (SiO2) with inclusions
mineral
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)
sedimentary
Orbicular jasper / brecciated jasper
Silica-rich microcrystalline quartz (chalcedony), commonly with iron oxides and altered volcanic fragments
metamorphic
Smoky Quartz (with Iron Oxidation)
Silicon Dioxide (SiO2)
mineral
Pink Dyed Agate
Silicon Dioxide (SiO2) with artificial pigment
sedimentary
Quartz-rich metamorphic rock, likely quartzite
Quartzite; predominantly microcrystalline quartz (SiO₂), possibly with mica or feldspar
metamorphic
Pink Granite River Rock
Phaneritic Felsic Igneous Rock (Granite)
igneous
Polished green stone, likely serpentine or altered basalt
Serpentine-group minerals, chiefly Mg₃Si₂O₅(OH)₄; exact identification requires testing
metamorphic
Limonite Concretion
FeO(OH)·nH2O (Hydrated Iron Oxide)
sedimentary
Dyed Agate
Silicon Dioxide (SiO2) with artificial pigment
sedimentary
Vesicular basalt (possible scoria)
Basaltic volcanic rock; chiefly plagioclase, pyroxene, and iron-rich minerals, with vesicles formed by trapped gas
igneous
Petrified Wood
Silicified wood (Quartz/Chalcedony replacement)
fossil
Rounded gray metamorphic cobble, likely quartzite or gneiss
Quartz-rich metamorphic rock; possibly quartzite (mostly SiO₂) or banded gneiss
metamorphic
Sandstone (Ferruginous)
Arenite (Fe-bearing Clastic Sedimentary Rock)
sedimentary
Granite
Granite (Felsic Plutonic Rock)
igneous
Chert (Iron-stained)
Chert (SiO2)
sedimentary
Smoky Quartz Geode Cluster
Silicon Dioxide (SiO2)
mineral
Polished agate/jasper pebble
Microcrystalline quartz (chalcedony), SiO₂, with likely iron-oxide and clay inclusions
mineral
Yellow Quartz
Silicon Dioxide (SiO2)
mineral
Chert (Cherty Shale / Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (Nodular or Massive Variety)
Cryptocrystalline Quartz (SiO2)
sedimentary
Tumbled chert or flint pebble
Microcrystalline quartz (SiO₂), likely chert; exact variety uncertain from the image
sedimentary
Granite
Phaneritic intrusive igneous rock
igneous
Granodiorite
Granodiorite (phaneritic intrusive igneous rock)
igneous
Desert Rose (also known as Sand Rose)
Gypsum (CaSO4·2H2O) or Barite (BaSO4) with sand inclusions
mineral
Polished brecciated jasper
Silicified breccia, chiefly microcrystalline quartz (SiO₂) with iron-oxide staining
mineral
Tumbled purple jasper (likely)
Microcrystalline quartz/chalcedony, SiO₂, colored by iron and other trace minerals
mineral
Water-worn basalt cobble
Basalt; chiefly plagioclase feldspar, pyroxene, and minor olivine/iron oxides
igneous
Bismuth Crystal
Bismuth (Bi)
mineral
Sandstone (with Liesegang rings or Oxidation)
Arenite (primarily Quartz SiO2 with Iron Oxide Fe2O3 staining)
sedimentary
Polished orbicular stone, likely granite or diorite
Granite–diorite, composed mainly of feldspar, quartz, and dark amphibole/biotite
igneous
Chert
Microcrystalline Quartz (SiO2)
sedimentary
Angel Aura Quartz (Treated Clear Quartz)
Silicon Dioxide (SiO2) coated with Vaporized Silver and Platinum
mineral
Weathered granite or granitic gneiss pebble
Granite; mainly quartz (SiO₂), feldspar, and mica, with possible gneissic alteration
igneous