Synthetic (Not A Rock Or Mineral)

White Quartz Pebble

Silicon Dioxide (SiO2)

Ferruginous Quartz

Silicon Dioxide (SiO2) with Limonite/Hematite inclusions

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Tiger's Eye (Unpolished)

Pseudomorph of Quartz after Crocidolite (SiO2)

Turquoise

Hydrous phosphate of copper and aluminum (CuAl6(PO4)4(OH)8·4H2O)

Amethyst

Silicon Dioxide (SiO2) with Iron impurities

Emerald In Matrix (Quartz/Calcite)

Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities

Turquoise

Hydrated phosphate of copper and aluminum, CuAl6(PO4)4(OH)8·4H2O

Quartz Vein in River Siltstone

Crystalline Quartz (SiO2) in Siliclastic Matrix

Chert (Septarian or Nodular variety)

Microcrystalline Quartz (SiO2)

Sandstone (Ferruginous Concretion)

Ferruginous Sandstone Concretion / SiO2 with Fe2O3 cement

Sandstone (Greywacke/Lithic Sandstone)

Arenite / Lithic Sandstone

Ethiopian Fire Opal

Hydrated Silica (SiO2·nH2O)

Banded Rhyolite (likely Green Jasper/Agate variety)

Silicon Dioxide (SiO2) with mineral inclusions

Sandstone

Arenite (SiO2 based clastic rock)

Quartz / Quartzite

Silicon Dioxide (SiO2)

Dendritic Agate

Chalcedony (SiO2) with manganese/iron oxide inclusions

Banded Gneiss (Variety of Gneiss)

Gneiss (specifically, a variety exhibiting prominent banding; mineral composition can vary, but often contains quartz, feldspar, mica, and amphibole)

Pegmatite

Granitic Pegmatite

Quartzite with inclusions

Quartzite (primarily SiO2)

Chalcedony (Agate)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Quartz Pebble (with Manganese dendrites/staining)

Silicon Dioxide (SiO2) with Manganese Oxide impurities

Gold Nugget

Native Gold (Au)

Blue Agate (Tumbled and Dyed)

Silicon Dioxide (SiO2) with likely organic dyes

Milky Quartz

Silicon Dioxide (SiO2)

Biotite (Black Mica)

Biotite - K(Mg,Fe)3(AlSi3O10)(OH)2

Collection of Minerals and Ores

Various (e.g., Uraninite (U3O8), Carbon (C), Native Gold (Au), Hematite (Fe2O3), Galena (PbS), etc.)

Leopard Skin Jasper

Jasper (Silicon Dioxide with impurities), SiO2

Serpentine (Nephrite-like River Cobble)

Serpentinite (Hydrous Magnesium Iron Silicate)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Granite

Phaneritic Plutonic Felsic Rock

Basalt

Basalt (Mafic volcanic rock)

Quartz Pebble

Silicon Dioxide (SiO2)

Ferruginous Quartz

Silicon Dioxide (SiO2) with Iron Oxide (Hematite/Limonite) inclusions

Chalcedony (Agate)

Silicon Dioxide (SiO2)

Amethyst

Silicon Dioxide with iron impurities (SiO2)

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Fe2O3 staining)

Wonderstone

Rhyolite (Silicon Dioxide with Iron Oxide impurities)

Gneiss (specifically Granite Gneiss)

Gneiss (High-grade Regional Metamorphic Rock)

Diorite (River Rock/Cobble)

Intermediate Plutonic Igneous Rock (Diorite)

Zinc Ore (Sphalerite in Matrix)

Sphalerite (Zn,Fe)S within a carbonate or silicate host rock

Limonite-stained Chert

Silicon Dioxide (SiO2) with Hydrated Iron Oxide (FeO(OH)·nH2O)