Jasper (brecciated or orbicular jasper)
Microcrystalline quartz (SiO₂), commonly mixed with hematite, goethite, chlorite, and other silicates
sedimentary
Category
Sedimentary (Volcanic)
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Quartz Geode
Silicon Dioxide (SiO2) in Geode formation
mineral
Chalcedony (Common Opal/Chert variety)
Silicon Dioxide (SiO2)
mineral
Weathered vesicular volcanic rock (likely scoria/tuff)
Basaltic scoria or vesicular volcanic tuff; exact identification is limited by the photograph
igneous
Red Jasper (or Agate/Jasper mixture)
Silicon Dioxide (SiO2) with Iron Oxide inclusions
mineral
Chert (Agatized/Chalcedony variety)
Microcrystalline Quartz (SiO2)
sedimentary
Yellow Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Tumbled jasper or porphyritic volcanic stone
Likely altered basalt/andesite with quartz, feldspar, and iron-oxide minerals
igneous
Ocean Jasper
Orbicular Jasper (Silicon Dioxide, SiO2)
sedimentary
Jasper
Silicon dioxide (SiO2)
sedimentary
Green Jasper
Silicon Dioxide (SiO2) with impurities of iron(II) silicate
sedimentary
Jasper (Green Jasper / River Jasper)
Silicon Dioxide (SiO2) with impurities
sedimentary
Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Red Jasper
Cryptocrystalline Quartz (SiO2 with Iron oxide inclusions)
sedimentary
Weathered vesicular volcanic rock, likely basaltic scoria
Vesicular basalt/scoria; chiefly plagioclase, pyroxene, olivine, and volcanic glass
igneous
Red Jasper
Silicon dioxide (SiO2) with iron oxide inclusions
sedimentary
Red Jasper
Silicon Dioxide (SiO2) with Hematite impurities
sedimentary
Jasper
Silicon Dioxide (SiO2)
sedimentary
Red jasper pebble
Microcrystalline quartz (SiO₂), colored chiefly by hematite/goethite
sedimentary
Jasper
SiO2
mineral
Jasper (Red/Brown)
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Weathered vesicular volcanic rock, likely pumiceous andesite or rhyolite
Pumiceous intermediate-to-felsic volcanic rock; commonly composed of plagioclase, quartz, alkali feldspar, and volcanic glass, with possible iron-oxide staining
igneous
Jasper Pendant
Silicon dioxide (SiO2) with impurities
Mineral/Sedimentary
Orbicular rhyolite (likely)
Silica-rich volcanic rock, chiefly quartz and feldspar with orbicular aggregates of feldspar, quartz, and mafic minerals
igneous
Fine-grained dark volcanic rock, likely basalt or scoria
Basaltic rock; predominantly plagioclase feldspar, pyroxene, and minor olivine/iron oxides
igneous
Chalcedony (possibly agate or common quartz)
Microcrystalline quartz, SiO₂
mineral
Vesicular basalt (possibly scoriaceous basalt)
Basalt, chiefly plagioclase feldspar, clinopyroxene, and iron-titanium oxides
igneous
Weathered volcanic rock fragment
Likely andesite or basaltic-andesite; exact identification requires fresh surface and testing
igneous
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Jasper
Silicon Dioxide (Microcrystalline Quartz, SiO2)
sedimentary
Jasper
Microcrystalline quartz (SiO2)
sedimentary
Red jasper
Jasper, an opaque microcrystalline variety of quartz (SiO₂), colored mainly by iron oxides
mineral
Tumbled carnelian (orange chalcedony)
Carnelian, a microcrystalline variety of quartz (SiO₂), commonly colored by iron oxides
gemstone
Red jasper pebble
Jasper, microcrystalline quartz (SiO₂), colored mainly by iron oxides
mineral
Agate Geode (Unopened)
Cryptocrystalline Quartz (SiO2) with Chalcedony
mineral
Carnelian
Carnelian (SiO2) - Chalcedony variety
mineral
Carnelian (Red Agate/Chalcedony)
Cryptocrystalline Quartz (SiO2) with Hematite impurities
mineral
Yellow Chalcedony (Agate/Carnelian variant)
Silicon Dioxide (SiO₂)
mineral
Jasper
Silicon Dioxide (Microcrystalline Quartz / Chalcedony)
sedimentary
Quartz (Druzy)
Silicon Dioxide (SiO2)
mineral
Tumbled red jasper
Microcrystalline quartz (chalcedony), primarily SiO₂, colored by iron oxides
mineral