Synthetic (Man Made Material Mimicking Natural Stone)

Ruby (in jewelry)

Corundum (Al2O3 with Chromium traces)

Polished/tumbled brown-and-white mineral fragment

Indeterminate; possibly quartz-rich jasper, brecciated jasper, or an iron-stained quartz mineral

Granite / Diorite (Granodiorite)

Granodiorite / Quartz Diorite

Chert (often called Flint or River Stone)

Microcrystalline alpha-quartz (SiO2)

Vesicular volcanic rock, likely weathered pumice or scoria

Pumice/scoria; predominantly volcanic glass and feldspar, with possible iron oxides

Coquina

Bioclastic Limestone

Granite

Granite (a common rock type, not a single mineral with a formula. Composed primarily of quartz, feldspar, and mica/amphibole).

Yellow Quartz (Citrine Quartz Pebble)

Silicon Dioxide (SiO2)

Smoky Quartz

Smoky Quartz (Silicon Dioxide - SiO2)

Diamond (Cut and Polished)

Diamond (pure Carbon, C)

Sandstone

Arenite (SiO2, often with CaCO3 or Fe2O3 cement)

Chert (specifically Flint or Nodular Chert)

Silicon dioxide (SiO2)

Green Slag Glass

Amorphous Silica / Glassy Blast Furnace Slag

Flint / Chert Pebble

Microcrystalline Quartz (SiO2)

Coquina

Coquina (Bioclastic Limestone)

Quartzite

Metamorphic Quartzite (SiO2)

Chert (and/or Flint)

Microcrystalline Quartz (SiO2)

Chert (and Agate/Chalcedony)

Microcrystalline Quartz (SiO2)

Carved Stone Turtle

Mixed stone carving

Shale with Vein Infillings

Shale (a fine-grained clastic sedimentary rock). The veins could be Calcite (CaCO3), Quartz (SiO2), or other minerals.

Chert (Jasper/Flint variety)

Silicon Dioxide (SiO2)

Diamond (as featured in jewelry)

Diamond (C - pure carbon)

Sandstone

Sandstone (Quartz-rich Arenite / SiO2)

Chert (specifically Flint Arrowhead)

Silicon dioxide (SiO2) - Microcrystalline Quartz

Asphalt Pavement (with aggregate)

Asphalt concrete

Blue Sapphire

Corundum (Al2O3)

Chert (Flint)

Silicon Dioxide (SiO2)

Chert (varietal: Flint/Jasper)

Silicon Dioxide (SiO2)

Pink Granite

Phaneritic Felsic Igneous Rock (Granite)

Rough Diamond

Diamond (Pure Carbon: C)

Granite

Granite (composed primarily of Quartz, Alkali Feldspar, and Plagioclase)

Ruby

Corundum (Aluminum Oxide with Chromium), Al2O3:Cr

Azurite-Malachite (often a mixed specimen)

Azurite: Cu3(CO3)2(OH)2; Malachite: Cu2(CO3)(OH)2. The specimen appears to be a natural mixture or intergrowth of these two minerals.

Carnelian/chalcedony rough

Microcrystalline quartz (SiO₂), iron-oxide-colored chalcedony

Seven Chakra Bonded Stone

Bonded composite of Red Jasper, Carnelian, Tiger's Eye, Aventurine, Lapis Lazuli, Amethyst, and Clear Quartz

Blue Topaz

Topaz [Al2SiO4(F,OH)2]

Cubic Zirconia

Zirconium Dioxide (ZrO2)

Chert

Chert (SiO2)

Red Sandstone

Arenite (Fe2O3 enriched)

Ruby (faceted gemstone)

Corundum (Al2O3 with Cr impurities)

Quartzite

Metamorphic quartz rock (SiO2)

Sandstone

Arenite (SiO2 based)