Man Made Material, Not A Natural Rock Or Mineral Specimen

Ferruginous Sandstone with Quartz Inclusions

Clastic Sedimentary Rock (Iron-rich Sandstone)

Citrine Quartz Crystal Cluster

Silicon Dioxide (SiO2) with iron impurities

Sandstone

Arenite (SiO2 based)

Blue Chalcedony (likely dyed)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Citrine Geode Fragment

Citrine (Silicon Dioxide with Iron Impurities), SiO2

Quartz (Citrine or Iron-Stained variety)

Silicon Dioxide (SiO2)

Basalt

Basalt (Mafic Extrusive Igneous Rock)

Druzy Quartz on Chalcedony Matrix

Silicon Dioxide (SiO2)

Basalt

Basalt (Mafic volcanic rock)

Red Sandstone

Arenite (Ferruginous Sandstone)

Limonite (Iron Ore)

Hydrous Iron Oxide (goethite, lepidocrocite)

Bauxite

Bauxite (Mixture of Al(OH)3, AlO(OH), and Fe2O3)

Quartz Geode/Druzy Quartz

Quartz (SiO₂)

Granite (tumbled pebble)

Granite (Plutonic Igneous Rock)

Sandstone with Algae Growth

Arenite with Chlorophyta/Lichen

Serpentinite (often called Jade or Nephrite substitute)

Serpentinite (composed primarily of Antigorite, Lizardite, or Chrysotile)

Citrine

Silicon Dioxide (SiO2)

Nuummite

Nuummite (Ortho-amphibole rock, primarily Anthophyllite and Gedrite)

Ruby (Raw/Rough)

Corundum (Al2O3 with Chromium trace)

Quartz (Smoky/Milky variety)

Silicon Dioxide (SiO2)

Chalcedony (Smoky Quartz or Agate nodule fragment)

Silicon Dioxide (SiO2)

Graphite

Graphite (Native Carbon, C)

Chert Nodule (Commonly known as Flint or River Rock)

Silicon Dioxide (SiO2)

Basalt (Water-worn Pebble)

Basalt (Mafic Extrusive Igneous Rock)

Chevron Amethyst

Silicon Dioxide (SiO2) with trace Iron impurities

Chert (Nodule)

Chert (Alpha-Quartz, SiO2)

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Olivine in Basalt matrix

Peridotite (Mg, Fe)2SiO4

Quartz Geode

Silicon Dioxide (SiO2) in Host Rock

Nuummite

Nuummite (Orthoamphibole rock composed of Anthophyllite and Gedrite, (Mg,Fe)7Si8O22(OH)2)

Sandstone

Arenite (composed primarily of SiO2)

Red Sandstone (Iron-Rich)

Arenite (Fe2O3)

Diamond (or Cubic Zirconia imitation)

Carbon (C) - Native Element

Limonite (Iron-rich Siltstone / Sandstone base)

Hydrous ferric oxide mixture (FeO(OH)·nH2O)

Ferruginous Sandstone (Ironstone)

Clastic sedimentary rock (SiO2 with Fe2O3/FeO(OH) cement)

Pink Granite

Felsic Plutonic Rock (primarily Quartz, Potassium Feldspar, and Plagioclase)

Serpentinite (often containing Jadeite/Nephrite)

Antigorite-rich Serpentine Rock, (Mg, Fe)3Si2O5(OH)4

Quartz (Milky or Iron-Stained)

Silicon Dioxide (SiO2)

Kyawthuite

Kyawthuite (Bi3+Sb5+O4)

Sandstone

Arenite (SiO2 based with mineral cement)

Tiger's Eye (Multicolor/Variegated)

Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxides)

Smoky Quartz with Amethyst

Silicon Dioxide (SiO2)