Mineral With Metamorphic Or Sedimentary Host

Agate

Silicon Dioxide (Chalcedony), SiO2

Dendritic Agate (or Dendritic Opal)

SiO2 (for Agate), SiO2·nH2O (for Opal)

Milky quartz-bearing rock (likely quartz vein fragment)

Quartz, silicon dioxide (SiO₂), with probable iron-oxide staining and dark host-rock inclusions

Chert on Volcanic Host Rock

Sedimentary Chert (SiO2) within Basalt or Andesite

Turquoise

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

Rough Star Sapphire (Corundum)

Al2O3 (Aluminum Oxide)

Quartz (Smoky Quartz variant)

Silicon Dioxide (SiO2)

Polished red jasper

Jasper, an opaque microcrystalline variety of quartz (SiO₂), colored mainly by iron oxides

Vein-filled Sedimentary Rock

Silicified sedimentary rock with quartz/calcite vein

Milky Quartz with Iron Staining

Silicon Dioxide (SiO2)

White quartz pebble

Quartz (silicon dioxide, SiO₂)

Turquoise

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

Lapis Lazuli (Raw Ore)

Na8[Al6Si6O24]n(S,Cl,SO4,OH)2 (Lazurite component)

Tumbled cream-colored stone, possibly quartz or calcite

Indeterminate from photograph; likely microcrystalline quartz (SiO₂) or calcite (CaCO₃)

Chalcedony (Common Agate)

Cryptocrystalline Quartz (SiO2)

Likely yellow calcite or sulfur-bearing mineral fragment

Calcite (CaCO₃) or native sulfur (S); identification is uncertain from the blurred image

Fluorite in Matrix

Calcium Fluoride (CaF2) with Quartz/Calcite matrix

Serpentinite

Serpentinite (Hydrated magnesium iron phyllosilicate)

Gold Ore in Matrix

Native Gold (Au) in Quartz/Host Rock

Quartz with Chlorite / Greenschist

Quartz vein in Greenschist (SiO2 with Chlorite group minerals)

Polished gray pebble, likely quartzite or chert

Quartzite (mostly SiO₂), tentative identification

Rough ruby-bearing corundum (identification uncertain)

Corundum (Al₂O₃), possibly ruby; the image alone cannot confirm ruby or distinguish it from other red-purple minerals.

Tumbled milky quartz

Quartz (silicon dioxide, SiO₂)

Geode (Unopened)

Chalcedony Geode (Hydrated Silicon Dioxide, SiO2)

Weathered serpentinite (likely)

Serpentinite; chiefly serpentine-group minerals, Mg₃Si₂O₅(OH)₄, with possible magnetite, carbonate, and chromite

Green aventurine quartz (tentative)

Quartz, SiO₂, with green fuchsite mica or other inclusions

Banded gneiss

Gneiss, commonly quartz–feldspar–mica gneiss

Quartz (Vein Quartz)

Silicon Dioxide (SiO2)

Zebra Jasper

Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions

Weathered metallic sulfide fragment, possibly pyrite-bearing rock

Likely iron sulfide (pyrite, FeS₂) in a weathered host rock; exact identification requires testing

Agate (within host rock)

Agate (Quartz variety SiO2)

Quartz Geode

Quartz (Silicon Dioxide, SiO2) in a Geode

Quartz Pebble with Epidote / Chlorite Inclusions

Silicon Dioxide (SiO2) with Epidote/Chlorite inclusions

Milky quartz

Quartz (SiO₂), likely massive milky quartz with minor iron-oxide staining and inclusions

Likely pyrite-bearing rock

Pyrite (FeS₂), possibly in a quartz-rich matrix; exact identification is uncertain from the image.

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) within Metasedimentary or Igneous Matrix

Precious Opal

Hydrated Silica (SiO2·nH2O)

Quartz Drusy on Matrix

Silicon Dioxide (SiO2)

Sapphire (Corundum)

Corundum (Al2O3)

Milky quartz

Quartz (silicon dioxide, SiO₂)

Milky quartz with iron-oxide staining

Quartz, silicon dioxide (SiO₂), cryptocrystalline-to-coarse crystalline aggregate

Chalcedony in Host Rock

Silicon Dioxide (SiO2)