Amethyst (Faceted)
Quartz (SiO2) with iron impurities
Mineral
Category
Synthetic (Man Made Glass)
Browse synthetic (man made glass) specimens identified by the Rock Identifier community.
Chert Pebble with Quartz Veining
Microcrystalline Quartz (SiO2)
sedimentary
Yellow Quartzite Pebble
Quartzite (SiO2)
metamorphic
Sunkissed Quartz or Hematoid Quartz
Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions
mineral
Milky Quartz with Iron Staining
Silicon Dioxide (SiO2)
mineral
Quartzite pebble
Quartzite (primarily SiO2)
metamorphic
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
mineral
Chert (with Quartz Vein)
Microcrystalline silica (SiO2)
sedimentary
Quartzite with Iron Inclusions
Metamorphosed Quartz Sandstone (SiO2 with Fe2O3)
metamorphic
Chert (Green variety)
Silicon Dioxide (SiO2)
sedimentary
Chert (Iron-stained)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Quartz on Basalt
Silicon Dioxide (SiO2) on Mafic Igneous Rock
Mineral on Igneous Rock
Chert (Red/Brown Variety)
Microcrystalline quartz (SiO2)
sedimentary
Flint (Chert)
Silicon Dioxide (SiO2)
sedimentary
Chert (Flint variety)
Chert (Cryptocrystalline Quartz, SiO2)
sedimentary
Quartzite
Quartzite (primarily SiO2)
metamorphic
Jasper with Quartz inclusions
Silicon Dioxide (SiO2)
sedimentary
Scoria
Vesicular Basaltic Glass (comprised primarily of volcanic glass/silica with plagioclase, pyroxene, and olivine crystals)
igneous
Fluorite
Calcium fluoride (CaF2)
mineral
Amethyst
Silicon Dioxide (SiO2) containing iron impurities
mineral
Ferruginous Slag (Iron Smelting Byproduct)
Fused Silicate Scoria (Amorphous mixture of FeO, SiO2, and CaO)
Antropogenic Glass / Mineraloid
Granite
Phaneritic Felsic Igneous Rock (primarily Quartz, Feldspar, and Mica)
igneous
Jasper with Quartz inclusion
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Citrine (Yellow Quartz)
Silicon Dioxide (SiO2)
Mineral
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Amethyst (Rough Quartz)
Silicon Dioxide (SiO2 with Iron impurities)
mineral
Amethyst
Silicon Dioxide (SiO2) with iron impurities
mineral
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
mineral
Quartzite (River Stone)
Quartzite (mainly SiO2 with iron oxide staining)
metamorphic
Quartz (Milky or Grainy Variety)
Silicon Dioxide (SiO2)
mineral
Quartz Vein in Gneiss or Basalt
Milky Quartz (SiO2) within Metamorphic Host Rock
Metamorphic or Igneous with Mineral Inclusion
Granite (Weathered)
Phaneritic Felsic Igneous Rock
Igneous
Pink Granite
Phaneritic intrusive felsic igneous rock
igneous
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert / Flint Nodules
Cryptocrystalline Quartz (SiO2)
sedimentary
Amethyst
SiO2 (Silicon Dioxide) - Purple variety of Crystalline Quartz
mineral
Amethyst (Quartz variety)
Amethyst - SiO2 (Silicon Dioxide with Iron impurities)
mineral
Clear Quartz
Silicon Dioxide (SiO2)
mineral
Obsidian
Obsidian (principally SiO2)
igneous
Jasper (specifically Red Jasper)
Silicon Dioxide with Iron Oxides (SiO2 + Fe2O3)
sedimentary
Iron-Stained Quartz Pebble
Silicon Dioxide (SiO2) with Iron Oxide (Limonite/Goethite) inclusions
mineral
Quartz Pebble (Iron-stained)
Silicon Dioxide (SiO2)
Mineral / Sedimentary setting