Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Category
Browse mineral like (natural glass) specimens identified by the Rock Identifier community.
Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Amethyst on Matrix
Amethyst (Silicon Dioxide, SiO2) with impurities of iron and irradiation
Banded Agate (specifically Eye Agate / Chalcedony)
Agate (Cryptocrystalline variety of Quartz, SiO2)
Vesicular Basalt (Lava Rock)
Basalt
Tumbled quartz-rich stone, likely druzy quartz or quartzite
Quartz (SiO₂), possibly quartzite with iron-oxide staining
Tumbled mahogany obsidian
Volcanic glass; primarily SiO₂ with iron-oxide-rich brown inclusions
Mohave Turquoise (Composite/Stabilized)
Hydrated copper aluminium phosphate (CuAl6(PO4)4(OH)8·4H2O) with stabilizing resin and metallic inclusions
Diamond (or Diamond Simulant)
Carbon (C) if diamond, various if simulant (e.g., Cubic Zirconia ZrO2)
Granite
Granite (Felsic Intrusive Igneous Rock)
Amethyst (Scepter Quartz)
Silicon Dioxide (SiO2) with Iron impurities
Diamond
Carbon (C)
Milky Quartz
Silicon Dioxide (SiO2)
Snowflake Obsidian
Obsidian with Cristobalite inclusions
Rough amber-like brown mineral specimen
Uncertain from photograph; possibly iron-stained quartz, common opal, or resinous amber
Chert Concretion (with typical hematite/limonite staining)
Sedimentary Concretion (SiO2 with FeO(OH)⋅nH2O)
Dyed Blue Agate
Silicon Dioxide (SiO2)
Mystic Topaz
Al2SiO4(F,OH)2 (Coated)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Quartz (likely) or a Quartzite Pebble
Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.
Weathered quartz-rich rock, possibly pegmatite or quartzite
Quartz (SiO₂)-rich aggregate; exact identification is uncertain from the photograph
Blue Topaz (specifically London Blue shade)
Topaz - Al2SiO4(F,OH)2
Smoky Quartz and Chalcedony Geode Fragment
Silicon Dioxide (SiO2)
Gneiss
Gneiss (foliated metamorphic rock)
Sandstone Pebble
Arenite (SiO2 with various cementing agents)
Diamond
Carbon (C)
Diamond (set in jewelry)
Diamond (Carbon, C)
Diamond inlaid in Jewelry
Carbon (C)
Diamond (Colorless/White)
Carbon (C)
Smoky Quartz (with Hematite inclusions)
Silicon Dioxide (SiO2)
Shiva Lingam Stone
Cryptocrystalline Quartz (Jasper/Basalt matrix)
Carved Stone Turtle
Mixed stone carving
Sandstone (Ferruginous)
Arenite (with Iron Oxide cement)
Chert / Flint
Microcrystalline Quartz (SiO2)
Sandstone (Quartzite-rich)
Clastic Sedimentary Rock (primarily SiO2)
Quartzite Pebble
Metamorphic Quartzite
Hag Stone
Perforated sedimentary rock (typically flint, chert, or limestone)
Milky Quartz with Iron Inclusions
Quartz (Silicon Dioxide, SiO2)
Clear Quartz
Quartz (Silicon Dioxide, SiO2)
Amethyst Quartz with Matrix
Silicon Dioxide (SiO2)
Shale
Shale (Fine-grained clastic sedimentary rock)
Chert (Commonly known as Flint/Jasper)
Microcrystalline Quartz (SiO2) with iron oxide inclusions
Yellow Ocher (Limonite)
Limonite (Hydrated Iron Oxide) - FeO(OH)·nH2O