Fulgurite (Sand-tube)
Fulgurite (Lechatelierite-rich fused sand)
Category
Browse mineral like (natural glass) specimens identified by the Rock Identifier community.
Fulgurite (Sand-tube)
Fulgurite (Lechatelierite-rich fused sand)
Sandstone (Ferruginous)
Arenite with Iron Oxide (Fe2O3) cement
Tektite
Natural impact glass
Milky Quartz
Crystalline Silicon Dioxide (SiO2)
Orange Quartz (Citrine Quartz)
Silicon Dioxide (SiO2) with iron impurities
Septarian Pebble
Septarian nodule / Concretion
Limonite with Quartz
Hydrated Iron Oxide Hydroxide, FeO(OH)·nH₂O with SiO₂
Diamond (or Simulant)
Carbon (C)
Quartz Pebble (Chalcedony / Agate)
Silicon Dioxide (SiO2)
Tumbled brecciated jasper
Silica-rich microcrystalline quartz/chalcedony (SiO₂), with iron-oxide and other mineral inclusions
Sandstone with Iron Oxide Coating
Arenite (SiO2 with Fe2O3 impurities)
Tumbled black stone, likely black obsidian
Obsidian — natural volcanic glass, primarily SiO₂
Opalite
Synthetic Opalized Glass
Ferrosilicon Slag (Industrial Vitrified Glass)
Vitreous Silicate Residue
Rough Citrine Quartz
Silicon Dioxide (SiO2) with ferric iron impurities
Opalite
Man-made Opalized Glass (Synthetic Glass)
Green Aventurine
Aventurine Quartz (SiO2 with inclusions of Fuchsite)
Colorless faceted gemstone, likely cubic zirconia
Cubic zirconia (synthetic zirconium dioxide, ZrO₂); possibly colorless quartz or laboratory diamond
Polished blue banded agate cabochon/ornamental slab
Microcrystalline quartz (chalcedony), SiO₂, with blue coloring or inclusions
Polished agate slice
Agate, a banded variety of chalcedony (microcrystalline SiO₂)
Rose Quartz (Dyed)
Silicon Dioxide (SiO2) with trace impurities
Yellow Quartz
Silicon Dioxide (SiO2)
Goldstone (blue-goldstone–style glass) beads
Artificial aventurine glass, typically silica glass with copper inclusions; not a natural mineral
Sandstone (Ferruginous)
Arenite (composed primarily of SiO2 with Fe2O3 staining)
Citrine Quartz
Silicon Dioxide (SiO2)
Chipped Glass/Plastic Fragment
Silicon dioxide (SiO2) for glass (amorphous) or various polymer compounds for plastic
Rose Quartz
Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Chert / Flint
Cryptocrystalline quartz (SiO2)
Granite
Granite (Mainly Quartz, Feldspar, and Mica)
Silver Nuggets (Natural or Cast)
Native Silver (Ag)
Limonite or Ironstone Nodule
Hydrated iron oxide-hydroxide (FeO(OH)·nH2O)
Amethyst Quartz
Silicon Dioxide (SiO2) with iron impurities
Yellow Quartz / Citrine Quartz
Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Smoky Quartz (Chlorite Inclusions)
Silicon Dioxide (SiO2) with trace Aluminum and Natural Irradiation
Green Glass Cullet / Recycled Glass
Amorphous Silicon Dioxide (SiO2) with various metal oxides
Yellow jasper or polished yellow chalcedony
Microcrystalline quartz, SiO₂, likely iron-stained jasper/chalcedony
Slag Glass
Silicon dioxide with impurities
Blue Sapphire
Corundum (Al2O3)
Pink Quartz / Sea Glass
Silicon Dioxide (SiO2)
Tumbled green aventurine (likely)
Quartz (SiO₂) with fuchsite or other green mica inclusions