Amethyst
SiO2 (Silicon Dioxide) - a variety of Quartz
Category
Browse industrial byproduct specimens identified by the Rock Identifier community.
Amethyst
SiO2 (Silicon Dioxide) - a variety of Quartz
Rose Quartz
Silicon Dioxide (SiO2)
White Marble
Recrystallized Calcite (CaCO3)
Topaz
Topaz (Al2SiO4(F,OH)2)
Chalcedony or Chert/Jasper with secondary mineral staining
SiO2 (for chalcedony/quartz) with possible secondary copper minerals (e.g., CuSiO3·nH2O for chrysocolla, Cu2(CO3)(OH)2 for malachite) or iron oxides/hydroxides.
Agate
Agate (a cryptocrystalline variety of Quartz, SiO₂)
Black Tourmaline
Schorl (Na(Fe2+)_{3}Al_{6} (BO_{3})_{3} (Si_{6}O_{18})(OH)_{4})
Magnetite
Magnetite (Fe3O4)
Amethyst (variety of Quartz)
SiO2 (Silicon Dioxide)
Quartz (Float/Abraded)
Quartz (SiO₂)
Peridot
Olivine (specific variety: gem-quality forsterite), (Mg,Fe)2SiO4
Oak-grain Laminate (Industrial/Decorative Furniture Finish)
Melamine Resin-impregnated Decorative Paper on Particleboard (Cellulose/Thermosetting Plastic)
Fluorite (often referred to casually as 'Fluorspar' in industrial contexts)
Fluorite (CaF2)
Rose Quartz
Rose Quartz (SiO₂)
River Rock / Stream Pebble
Fluvial Clast / Rounded Sedimentary Particle
Aventurine (likely Green Aventurine)
Aventurine (a variety of quartz, SiO₂, with common inclusions of fuchsite)
Biotite Schist (likely)
Biotite Schist (rock), Biotite (mineral)
Quartz (in a rock matrix)
Quartz (SiO2)
Agate (or Chalcedony)
SiO2 (Silicon Dioxide) - a cryptocrystalline variety of quartz
Agate
Chalcedony (cryptocrystalline quartz)
Clay (as a rock-forming material)
Clay minerals (e.g., Kaolinite group, Smectite group, Illite group, Chlorite group)
Tourmaline (likely Schorl)
Tourmaline Group Mineral (e.g., Schorl for black varieties); (Na,Ca)(Li,Mg,Fe,Mn,Al)3Al6(BO3)3Si6O18(OH)4
Quartz (milky variety)
SiO2 (Silicon Dioxide)
Amethyst
Quartz (SiO2) with trace iron impurities
Chert
Chert (microcrystalline quartz, SiO2)
Almandine Garnet
Almandine (Fe3Al2(SiO4)3)
Fluorite Bracelet (light green beads) and possibly Lavender Jadeite (purple bead)
Fluorite: CaF₂ (Calcium Fluoride); Jadeite: NaAlSi₂O₆ (Sodium Aluminum Silicate)
Serpentine Jade (New Jade/Olive Jade)
Serpentinite (a rock composed primarily of serpentine minerals) / Mg3Si2O5(OH)4 for Antigorite and Lizardite
Quartz with Iron Stains
Quartz (SiO2) with iron oxide/hydroxide staining
Brown Jasper (Likely)
Jasper (Cryptocrystalline Silicon Dioxide - SiO2)
Smoky Quartz
Smoky Quartz (SiO2)
Anthracite Coal
Anthracite (a form of coal, primarily carbon)
Chert (Jasper-like)
SiO2 (Cryptocrystalline Quartz)
Jasper (yellow/cream variety)
SiO₂ (Cryptocrystalline Quartz)
Marble
Marble (primarily Calcite, CaCO3 or Dolomite, CaMg(CO3)2)
Aragonite (variety 'Flos Ferri')
Aragonite (CaCO3)
Quartz (variety of colors)
SiO2 (Silicon Dioxide)
Chalcedony
Chalcedony (SiO₂)
Sandstone (Pebble/Conglomerate fragment)
Sandstone (clastic sedimentary rock)
River/Stream Pebble
Clast / Detrital Grain / Rounded Sedimentary Particle (Compositionally variable, commonly Quartz, Feldspar, Chert, or other resistant rock fragments)
Amethyst
Quartz (SiO2) variety
Banded Iron Formation
Banded Iron Formation (BIF)