Green tourmaline (likely elbaite)
Tourmaline-group cyclosilicate; likely elbaite, Na(Li,Al)3Al6(BO3)3Si6O18(OH)4
Category
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Green tourmaline (likely elbaite)
Tourmaline-group cyclosilicate; likely elbaite, Na(Li,Al)3Al6(BO3)3Si6O18(OH)4
Chert (or Flint)
Chert (cryptocrystalline quartz), SiO2
Tumbled chalcedony (likely blue-gray agate)
Cryptocrystalline quartz, SiO₂; chalcedony/agate variety
Ruby-in-Fuchsite cabochon/tower
Corundum (ruby, Al₂O₃) in fuchsite-bearing mica schist; commonly with chromite and quartz
Carved smoky quartz (likely)
Quartz, silicon dioxide (SiO₂), smoky variety
Clear quartz crystal pendant
Quartz (silicon dioxide, SiO₂)
Vesicular basalt (likely)
Basalt; chiefly plagioclase, clinopyroxene, and olivine, with possible iron-oxide alteration
Likely basalt
Mafic volcanic rock, chiefly plagioclase and pyroxene, commonly with minor olivine and magnetite
Marble
Marble (metamorphosed limestone/dolostone). Predominantly composed of Calcite (CaCO3) for marble derived from limestone, or Dolomite (CaMg(CO3)2) for marble derived from dolostone.
Mother of Pearl (Nacre)
Calcium Carbonate (primarily aragonite, with conchiolin)
Iron-stained quartz-rich breccia (probable)
Hydrothermal quartz–iron oxide breccia; mainly SiO₂ quartz with iron oxides/hydroxides (hematite/goethite)
Obsidian
Obsidian (volcanic glass, amorphous silica rich rock)
Mixed Gemstone Beaded Jewelry
Various minerals (e.g., Quartz varieties like Rose Quartz, Amethyst; Peridot; Garnet; etc.)
Emerald (Rough)
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
Quartz geode
Quartz (SiO₂), likely a chalcedony-lined geode with druzy quartz
Mounted clear gemstone, likely cubic zirconia
Cubic zirconia (zirconium dioxide, ZrO₂), synthetic; exact stone cannot be confirmed from the image
Iron-stained brecciated quartz vein rock
Quartz-rich hydrothermal breccia; predominantly SiO₂ with iron oxides/hydroxides (hematite, goethite) and likely minor host-rock minerals
Quartz-rich metamorphic rock, likely quartzite
Quartzite; predominantly crystalline SiO₂, with minor gray mica/graphite or accessory minerals
Stainless Steel Spoon
Iron-Chromium Alloy (Fe + Cr + Ni)
Vesicular basalt (likely weathered lava rock)
Vesicular basalt; primarily plagioclase feldspar, pyroxene, and volcanic glass, with possible iron-oxide alteration
Red Swirl Beads (Likely Resin or Glass, simulating Red Jasper or Agate)
N/A (for the beads as pictured); Red Jasper: SiO2 (Chert variety); Red Agate: SiO2 (Chalcedony variety)
Rose Quartz (likely carved)
Rose Quartz (SiO2)
Rose Quartz Carving
Quartum roseum (Variety of Quartz, SiO2)
Pumice
Pumice, a highly vesicular volcanic glass, commonly rhyolitic to dacitic in composition
Serpentinite
Serpentinite (composed primarily of serpentine-group minerals like antigorite, chrysotile, and lizardite; chemical formula varies but generally Mg3Si2O5(OH)4)
Mica schist (possibly garnet–mica schist)
Muscovite–biotite schist; chiefly quartz, feldspar, muscovite, and biotite
Goldstone
Not a natural mineral or rock. It is an ornamental glass.
Mica-rich schist
Muscovite–biotite schist, commonly quartz-bearing
Mica-rich metamorphic rock, likely schist
Muscovite–biotite schist, possibly phyllite; composition dominated by mica and quartz
Calcite (commonly referred to as Orange Calcite or Honey Calcite given its color)
Calcite
Scoria
Scoria (a vesicular basalt or andesite)
Rhodonite
Rhodonite (MnSiO3)
Lazulite
Lazulite (Mg,Fe2+)Al2(PO4)2(OH)2
Yellow faceted gemstone, likely citrine or yellow sapphire
Uncertain; probable quartz (SiO₂) or corundum (Al₂O₃)
Fossilized gastropod (likely nerite or related sea snail)
Gastropoda; shell composed originally of aragonite/calcite, commonly replaced or infilled by calcite
Polished brown chalcedony (likely carnelian or jasper)
Microcrystalline quartz, SiO₂; iron oxides produce the brown coloration
Chert
Silicon dioxide (SiO2)
Granite
Granite
Tumbled sodalite with white calcite veining
Sodalite, Na8(Al6Si6O24)Cl2, commonly intergrown with calcite, CaCO3
Tumbled serpentine
Serpentine-group minerals, chiefly antigorite, lizardite, or chrysotile; approximately Mg₃Si₂O₅(OH)₄
Chalcedony / milky quartz flake
Microcrystalline quartz (SiO₂), likely chalcedony; possibly a worked quartzite or chert fragment
Quartz (Rock Crystal) with minor impurities
Quartz (SiO2)