Petrified Wood
Silicified Wood (SiO2)
Category
Browse mineral (cryptocrystalline quartz) specimens identified by the Rock Identifier community.
Petrified Wood
Silicified Wood (SiO2)
Milky quartz pebble
Quartz (silicon dioxide, SiO₂)
Chocolate Jasper
Microcrystalline Quartz (SiO2) with impurities
Jasper
Microcrystalline Quartz (SiO2)
Quartzite
Hydrothermal Quartz or Quartzite (SiO2)
Tumbled Mixed Gemstones and Rocks
Various mineral species including quartz (SiO2) and silicate minerals
Chert (often found as Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chrysocolla on Matrix
Hydrated copper phyllosilicate (Cu,Al)2H2Si2O5(OH)4·nH2O
River Pebble
Weathered Rock Fragment
Petrified Wood
Silicified Wood (primarily SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Agate (Polished Cabochon Slice)
Silicon Dioxide (SiO2)
Chert (with Quartz Veining)
Microcrystalline Quartz (SiO2)
Yellow Chalcedony
Chalcedony (a cryptocrystalline variety of Quartz, SiO₂)
Yellow Quartz / Chalcedony Pebble
Silicon Dioxide (SiO2)
Chert (Cherty Limestone / Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Jasper
Jasper (Cryptocrystalline Quartz; SiO2)
Chalcedony (specifically Agate or Carnelian variety)
Cryptocrystalline Silica (SiO2)
Poppy Jasper
Microcrystalline Quartz (SiO2) with mineral inclusions
Chrysocolla
Hydrated copper silicate (Cu,Al)2H2Si2O5(OH)4·nH2O
Lake Superior Agate
Silicon Dioxide (Cryptocrystalline Quartz), SiO2
Botryoidal Chalcedony (Agate)
Silicon Dioxide (SiO2)
Chert (Flint nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Flint variety)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert (often called Flint or Jasper based on color)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (specifically Gray Chert/Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Quartzite and Jasper Pebbles
Quartzite (re-crystallized Quartz) and Cryptocrystalline Quartz (SiO2)
Chalcedony (likely agate or chert)
Microcrystalline quartz, SiO₂
Petrified Wood
Silicified Wood (Permineralized wood)
Agate
Silicon Dioxide (SiO2) - Chalcedony variant
Blue Chalcedony
Silicon Dioxide (SiO2)
Chert (Jasper variety)
Microcrystalline Quartz (SiO2)
Tumbled brown stone, likely jasper or iron-stained quartz
Microcrystalline quartz (SiO₂), possibly chalcedony/jasper with iron-oxide inclusions
Polished brecciated jasper
Jasper (microcrystalline quartz, SiO₂), likely iron-oxide-rich breccia
Jasper
Microcrystalline Quartz (SiO2)
Chert (specifically Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Tumbled brown jasper (likely iron-rich chalcedony)
Jasper, opaque microcrystalline quartz (SiO₂), commonly colored by iron oxides
Tumbled jasper (likely brecciated or orbicular jasper)
Microcrystalline quartz (chalcedony), SiO₂, with iron-oxide and other mineral inclusions
Orbicular jasper (likely ocean jasper)
Silica-rich microcrystalline quartz/chalcedony with iron-oxide and other mineral inclusions; commonly classified as orbicular jasper
Agate / Chalcedony Pebble
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)