Mineral, Part Of A Rock

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic volcanic rock including secondary mineral infills)

Granite Cobble

Granite (Phaneritic Igneous Rock)

Druzzy Quartz on Matrix

Silicon Dioxide (SiO2)

Gneiss

Gneiss (a type of metamorphic rock)

Gneiss (with Mica and Quartz)

Gneissic Metamorphic Rock

Sandstone (Pebble)

Arenite (primarily SiO2)

Sandstone

Arenite (SiO2 principal)

Sandstone

Arenite (primarily SiO2)

Sandstone

Clastic sedimentary rock (primarily SiO2)

Sandstone

Arenite (primarily SiO2)

Blue Chalcedony

Silicon Dioxide (SiO2)

Sandstone

Arenite (composed primarily of SiO2)

Sandstone (with man-made markings)

Arenite (composed primarily of Quartz, SiO2)

Sandstone

Arenite (primarily SiO2)

Sandstone (Picture Sandstone)

Sandstone (primarily Quartz with Iron Oxide impurities)

Granite

Granite (a felsic intrusive igneous rock)

Granodiorite

Granodiorite (intermediate plutonic rock)

Agate

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Sandstone (likely with Quartz Veining)

Arenite (primarily SiO2)

Quartz (Milky Quartz vein fragment)

Silicon Dioxide (SiO2)

Quartz Crystal (specifically a Double-Terminated variety)

Silicon Dioxide (SiO2) - Low Quartz

Amygdaloidal Basalt with Zeolite/Quartz Infill

Amygdaloidal Basalt (Host: (Mg,Fe)2SiO4 / CaAl2Si2O8; Infill: SiO2 or Na2Al2Si3O10·2H2O)

River Pebble (Likely Chert or Fine-Grained Sandstone/Quartzite)

Siliciclastic clast (likely Chert or Quartzarenite/Quartzite pebble)

River Stone (Granitic Gneiss)

Foliated Granitic Gneiss

Red Sandstone (Old Red Sandstone)

Ferruginous Sandstone (SiO2 + Fe2O3)

Bauxite

Bauxite (Al(OH)3, AlO(OH))

Basalt with Vesicles

Vesicular Basalt (comprising Plagioclase Feldspar, Pyroxene, and Olivine)

Orbicular Granite

Orbicular Granidiorite / Plutonic Igneous Rock

Basalt

Basalt (extrusive igneous rock)

Pyrite on Quartz matrix

Iron Disulfide (FeS2) on Silicon Dioxide (SiO2)

River Rock

Sedimentary Rock (various compositions)

Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Agate

Silicon Dioxide (SiO2)

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Sandstone

Arenite (SiO2 based with various mineral cements)

Sandstone (Ferruginous)

Arenite with Iron Oxide cement (SiO2 + Fe2O3)

Basalt with Quartz/Feldspar Inclusions

Amygdaloidal or Porphyritic Mafic Volcanic Rock with Siliceous Veining

Amygdaloidal Basalt with Agate/Chalcedony Infills

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

Limestone Breccia

Sedimentary Breccia (Calcareous)

Sandstone (with Iron Staining)

Clastic Sedimentary Rock (primarily Quartz, SiO2)

Sandstone (likely Ferruginous)

Sandstone (SiO2 with iron oxides)

Shale

Fissile mudrock (composed primarily of clay minerals and quartz)