Sedimentary (Physico Chemical Precipitate)

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

Quartz (Milky/Common)

Silicon Dioxide (SiO2)

Quartzite Pebble

Quartzite (primarily SiO2)

Iron Ore / Ironstone Concretion

Mixture of iron oxide/hydroxide minerals, likely some combination of Hematite (Fe2O3), Goethite (α-FeOOH), and Limonite (a general term for hydrated iron oxides of variable composition) or potentially Bauxite (a mixture of aluminum hydroxides, often with iron oxides, (Al(OH)3) and FeO(OH)). The visual characteristics strongly suggest iron-rich material.

Quartz (Milky/Common)

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Clear Quartz

Quartz (Silicon Dioxide, SiO2)

Quartz (Milky/Common)

Silicon Dioxide (SiO2)

Quartz (River Pebble)

Silicon Dioxide (SiO2)

Quartz (Milky Quartz / Greenish Quartz)

SiO2 (Silicon Dioxide)

Quartz pebble

Silicon Dioxide (SiO2)

Quartz / Quartz Cluster

Silicon Dioxide (SiO2)

Banded Jasper (Chert)

Silicon Dioxide (SiO2) - variety of Chalcedony

Amygdaloidal Basalt

Vesicular Basalt with secondary mineral infilling (commonly Zeolite, Calcite, or Quartz)

Malachite

Copper carbonate hydroxide Cu2CO3(OH)2

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Agate (specifically a Thunderegg/Agate Nodule)

Cryptocrystalline Quartz (SiO2)

Onyx

Onyx (a variety of Chalcedony, SiO₂)

Quartz (Water-worn pebble)

Silicon Dioxide (SiO2)

Azurite with Malachite

Azurite: Cu3(CO3)2(OH)2 / Malachite: Cu2CO3(OH)2

N/A - Image is non-geological

Acrylonitrile Butadiene Styrene (ABS) or Polypropylene (PP)

Shale or Mudstone (Based on appearance)

Shale (fine-grained, laminated fissile sedimentary rock) / Mudstone (fine-grained, non-fissile sedimentary rock)

Pebble (likely Sandstone or Granitic Pebble)

Clastic Sediment (or specific rock type, e.g., Arenite, Granitoid Pebble)

Amygdaloidal Basalt

Basalt with secondary mineral infilling (commonly Zeolite, Calcite, or Quartz)

Fluorite (likely Fluorite on Quartz/Matrix)

Calcium Fluoride (CaF2)

Quartz (Druzy or Crystalline variety)

Silicon Dioxide (SiO2)

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic volcanic rock including secondary mineral infills)

Paper (Cellulose)

Cellulose (C6H10O5)n

Yellow Ocher / Limonite

FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide)

Quartz / Quartzite

Silicon Dioxide (SiO2)

Quartz (Smoky/Milky variety)

Silicon Dioxide (SiO2)

Quartz (specifically Milky or Clear Quartz fragment)

Silicon Dioxide (SiO2)

Quartz / Quartzite

Silicon Dioxide (SiO2)

Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Quartz / Vein Quartz

Quartz (Silicon Dioxide, SiO2)

Quartzite Pebble

Quartzite (primarily SiO2)

Quartz

Silicon Dioxide (SiO2)

Quartz (Milky/Common variety)

Silicon Dioxide (SiO2)

Tiger's Eye

Tiger's eye (Pseudomorph of Quartz after Crocidolite), SiO2

Quartz (Sand Grain size)

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz (Milky/Smoky variety)

Silicon Dioxide (SiO2)