Metamorphic Or Igneous

Ruby

Corundum (Al2O3:Cr)

Polished blue-gray mineral specimen, likely galena-bearing ore

Galena (PbS), possibly mixed with quartz/calcite and secondary copper minerals

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Milky quartz vein fragment

Quartz, silicon dioxide (SiO₂)

Milky Quartz

Silicon Dioxide (SiO2)

Milky quartz (iron-stained quartz)

Quartz, silicon dioxide (SiO₂)

Green Aventurine

Quartz (Silicon Dioxide, SiO2) with fuchsite inclusions

Quartz (Smoky/Clear variety)

Silicon Dioxide (SiO2)

Agate

Silicon dioxide (Chalcedony), SiO2

Milky Quartz (Quartz Vein)

Silicon Dioxide (SiO2)

Faceted yellow gemstone, likely citrine

Citrine (quartz), SiO₂; possibly yellow sapphire or synthetic glass without testing

Massive Quartz with Host Rock

Silicon Dioxide (SiO2)

Pyrite in Quartz

Iron Sulfide (FeS2) in Silicon Dioxide (SiO2)

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) within Metasedimentary or Igneous Matrix

Ruby

Corundum (Al2O3:Cr)

Ferruginous Quartz

Silicon Dioxide with Iron Oxide (SiO2 + Fe2O3)

Red faceted gemstone ring

Likely synthetic ruby or red spinel; exact identification requires testing

Hematite

Iron(III) oxide (Fe2O3)

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz with Matrix

Silicon Dioxide (SiO2)

Hematite

Iron(III) oxide (Fe2O3)

Calcite

Calcite (CaCO3)

Quartz (Pinkish-Orange Variety)

Crystalline Silicon Dioxide (SiO2)

Weathered quartz-rich metamorphic rock, likely quartzite or gneiss

Quartzite/gneiss; chiefly quartz (SiO₂) with feldspar and mica/iron oxides

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Gold (Processed)

Gold (Au)

Rose Quartz

Rose Quartz (SiO2)

Blue Sapphire and Diamond (Set in Metal)

Corundum (Al2O3) and Diamond (C)

Green Calcite

Calcite (CaCO3)

Granite Gneiss or Granitoid River Rock

Granitoid / Gneiss

Quartz River Pebble with Algae

Silicon Dioxide (SiO2) with organic biofilm

Quartzite (river pebble) and Gabbro (crushed rock)

Quartzite (metamorphosed Quartz Sandstone, SiO2) and Gabbro (Plagioclase-Clinopyroxene rock)

Sapphire (Corundum variety)

Sapphire (Al₂O₃)

Quartzite or Quartz pebble

SiO2 (Silicon dioxide) with impurities

Riverstone (Quartzite/Granite Cobble)

Silicon Dioxide (SiO2) based Quartzite or Silicate-rich Granite

Rutilated Quartz

SiO2 with TiO2 inclusions (Rutile)

Calcite

Calcite (CaCO3)

Greenish rock with white veins, possibly epidote or chlorite bearing rock with quartz/calcite veins

Altered mafic rock or Epidosite

Mixed beach pebbles; likely quartzite, granite, and iron-stained metamorphic rock

Predominantly quartzite (SiO₂), granite (quartz–feldspar–mica), and weathered iron-rich rock

Fulonite (Fulgurite-like)

Fulgurite (SiO2 fused silica/lechatelierite)

Quartz (Druzy) in host rock

SiO₂ (Silicon Dioxide) as Quartz, with unspecified host rock components (likely silicates and iron oxides)

Quartz Vein in Host Rock (often Granite or Schist)

Silicon Dioxide (SiO2) within host matrix