Igneous Rock (Volcanic Glass)

Basalt

Basalt (Mafic Extrusive Igneous Rock)

Amygdaloidal Basalt with Agate/Chalcedony Infills

Amygdaloidal Basalt (Composition: SiO2 and (Mg,Fe)2SiO4 in matrix; SiO2 in amygdule)

Basalt

Basalt (SiO2 percentage between 45% and 52%)

Amethyst

SiO2 (Silicon Dioxide with iron impurities)

Basalt

Mafic Igneous Rock (primarily Plagioclase Feldspar and Pyroxene)

Vesicular Basalt (Scoria)

Extrusive Mafic Volcanic Rock (FeO-SiO2-MgO)

Sunstone

Oligoclase or Andesine (Plagioclase Feldspar) - (Ca, Na)((Al, Si)2Si2O8)

Scoria (Lava Rock)

Scoriaceous Basalt

Milky Quartz (among River Rock)

Quartz (Silicon Dioxide, SiO2)

Spinifex Textured Komatiite

Komatiite (Mg-rich ultramafic volcanic rock)

Clear Quartz

Silicon Dioxide (SiO2)

Flowerstone

Porphyritic Basalt or Porphyritic Andesite

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Flower Agate

Chalcedony (Silicon Dioxide, SiO2) with Opaque Spherulitic Inclusions

Wishing Stone (Basalt or Siltstone with Quartz/Calcite Vein)

Basalt (SiO2+MgO+FeO) or Siltstone with a Quartz (SiO2) or Calcite (CaCO3) vein

Jasper

Jasper (Silicon Dioxide, SiO2)

Dolerite (Diabase)

Dolerite / Diabase

Basalt

Basalt (Phaneritic/Aphanitic Mafic Igneous Rock)

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Basalt

Mafic volcanic rock, primarily composed of Plagioclase, Pyroxene, and Olivine

Porphyry (Flower Stone)

Porphyritic Basalt or Andesite

Quartz

Silicon dioxide (SiO2)

Red Scoria (Lava Rock)

Vesicular Basalt / Scoria

Clear Quartz

Silicon Dioxide (SiO2)

Yellow Quartz Pebble

Silicon Dioxide (SiO2)

Obsidian

Obsidian (Amorphous volcanic glass, SiO2 rich)

Pink Granite (Water-worn Cobble)

Phaneritic Felsic Intrusive Igneous Rock

Jasper

Jasper (Silicon Dioxide, SiO2)

Basalt

Basalt (containing Pyroxene, Plagioclase Feldspar, and Olivine)

Chert (Jasper/Agate variety)

Microcrystalline Quartz (SiO2)

Obsidian

Obsidian (Volcanic Glass, SiO2 + impurity isotopes)

Banded Chalcedony (Agate)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Agate

Silicon Dioxide (SiO2) - variety of Chalcedony

Snowflake Obsidian

Volcanic Glass with Cristobalite inclusions (70–75% SiO2)

Obsidian

Obsidian (volcanic glass), predominantly Silicon Dioxide (SiO2)

Vesicular Basalt (River Pebble)

Vesicular Basalt

Quartz (Druzy/Macro-crystalline)

Silicon Dioxide (SiO2)

Amethyst

Amethyst (Silicon Dioxide, SiO2)

Chalcedony (Botryoidal)

Silicon Dioxide (SiO2)

Green Apophyllite and Stilbite on Quartz Cluster

Apophyllite-(K) (KCa4(Si8O20)(F,OH)·8H2O), Stilbite-Ca (NaCa4(Si27Al9)O72·28H2O), Quartz (SiO2)

Basalt (Porphyritic)

Porphyritic Mafic Extrusive (Basalt)

Basalt

Mafic Volcanic Rock (Primarily Plagioclase and Pyroxene)