Weathered porphyritic volcanic rock, likely andesite
Porphyritic andesite (tentative; plagioclase ± pyroxene/amphibole in a fine groundmass)
igneous
Category
Sedimentary (Volcanic)
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Pumice
Vesicular volcanic glass, typically rhyolitic to dacitic; mainly silica-rich volcanic glass with feldspar and minor quartz or pyroxene
igneous
Red Jasper (Tumbled)
Silicon Dioxide (SiO2) with Hematite inclusions
sedimentary
Quartz Geode Fragment
Silicon Dioxide (SiO2)
sedimentary
Opal
Hydrated silica (SiO2 · nH2O)
mineraloid
Opal
Hydrated Silica (SiO2·nH2O)
mineral
Jasper or Agate pendant
Silicon dioxide (SiO2)
Mineral
Polished ocean jasper (orbicular jasper)
Orbicular jasper; chiefly microcrystalline quartz (SiO₂) with chalcedony, iron oxides, and accessory minerals
sedimentary
Quartz Geode/Vug in Host Rock
SiO2 (Silicon Dioxide) in various host rocks
mineral
Jasper
Silicon dioxide (SiO2)
sedimentary
Chert (Yellow Jasper/Common Opal variety)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Jasper/Agate variant)
Microcrystalline Quartz (SiO2) with iron oxide inclusions
sedimentary
Bumblebee Jasper
Calcite-bearing Volcanic Tuff containing Orpiment (As2S3) and Realgar (As4S4)
sedimentary
Jasper (Green Jasper / Moss Agate variety)
Silicon Dioxide (SiO2)
sedimentary
Yellow Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Yellow Jasper
Silicon Dioxide (SiO2) with iron oxide impurities
sedimentary
Tumbled jasper
Microcrystalline quartz (SiO₂), commonly with hematite/goethite and other iron oxides
metamorphic
Chalcedony (variations like Agate or Jasper)
Chalcedony (SiO₂ - microcrystalline quartz)
Mineral
Orbicular rhyolite (likely)
Rhyolite, a silica-rich volcanic rock; commonly quartz, alkali feldspar, plagioclase, and iron-rich alteration minerals
igneous
Black Jasper
Silicon Dioxide (SiO2) with carbon/iron impurities
sedimentary
Purple Chalcedony
Silicon Dioxide (SiO2)
mineral
Quartz Geode
Silicon Dioxide (SiO2)
mineral
Polished black stone, likely hematite or black jasper
Hematite (Fe₂O₃) or opaque chalcedony/jasper (SiO₂); image-only identification is uncertain
mineral
Bumblebee Jasper (technically a type of Agate/Anhydrite)
Calcite and Anhydrite with inclusions of Realgar and Orpiment (As2S3)
sedimentary
Jasper with Hematite Inclusions
Silicon Dioxide (SiO2) with Ferric Oxide (Fe2O3)
sedimentary
Orbicular jasper (polished pebble)
Silicified volcanic or sedimentary breccia; chiefly microcrystalline quartz/chalcedony (SiO₂) with iron-oxide and clay-rich matrix
sedimentary
Red Jasper
Silicon Dioxide (SiO2) with Iron Oxide inclusions
sedimentary
Chert (Jasper/Opaline variety)
Silicon Dioxide (SiO2)
sedimentary
Red Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Quartz Geode with Calcite/Siderite
Crystalline Silicon Dioxide (SiO2) with Carbonate inclusions
mineral
Greenstone
Metabasalt
metamorphic
Quartz Geode
Crystalline Silicon Dioxide (SiO2)
mineral
Carnelian
Carnelian (variety of Chalcedony, SiO2)
mineral
Black Onyx
Silicon Dioxide (SiO2)
mineral
Green Opal or Yellow Opal
Hydrated Silica (SiO2·nH2O)
mineraloid
Jasper
Jasper (Silicon Dioxide, SiO2)
Mineral
Carnelian
Carnelian (variety of Chalcedony, SiO2)
mineral
Jasper
Jasper (Silicon Dioxide, SiO2)
mineral
Vesicular basalt (likely amygdaloidal basalt)
Basalt, a mafic volcanic rock composed mainly of plagioclase feldspar, clinopyroxene, and commonly olivine; vesicles are partly mineral-filled amygdules.
igneous
Tumbled red jasper
Jasper, an opaque microcrystalline variety of quartz (SiO₂), commonly colored by iron oxides
mineral
Sulfur (Sulphur)
Sulfur (S8)
mineral