Mineral With Artificial Coating

Smoky quartz crystal (tentative)

Quartz, silicon dioxide (SiO₂), likely smoky variety

Smoky Quartz

Silicon Dioxide (SiO2)

Glass

Amorphous Silicon Dioxide (SiO2)

Quartz with Iron Staining

Silicon Dioxide (SiO2) with Hematite/Limonite inclusions

Milky Quartz with Iron Staining

Silicon Dioxide (SiO2)

Banded calcite (likely honey/orange calcite)

Calcite, CaCO₃

Milky quartz-rich rock

Quartz, SiO₂; possibly quartzite or massive vein quartz

Tumbled or naturally broken quartz crystal

Quartz (silicon dioxide, SiO₂)

Milky quartz crystal with iron-oxide inclusions

Quartz (SiO₂), likely limonite/goethite-stained inclusions

Milky quartz

Quartz (SiO₂), commonly massive or vein quartz

Milky quartz vein fragment

Quartz, silicon dioxide (SiO₂)

Mystic Topaz

Aluminum silicate fluoride hydroxide with titanium coating (Al2SiO4(F,OH)2)

Quartz-rich breccia or vein quartz specimen

Microcrystalline and crystalline quartz (SiO₂), possibly with iron-oxide staining and minor sulfides

Dyed Agate

Microcrystalline Quartz (SiO2) with artificial pigment

Ferruginous Quartz

Silicon Dioxide with Iron Oxide Inclusions (SiO2)

Vesicular basalt (likely scoriaceous basalt)

Basalt, primarily plagioclase, pyroxene, and commonly olivine; vesicles may be lined with secondary minerals

Blue Quartzite (Dyed)

Metamorphosed Quartz-rich Sandstone (SiO2 with organic dye)

Quartz geode/druse specimens

Quartz, silicon dioxide (SiO₂), likely iron-stained drusy quartz in a vuggy host rock

Tumbled labradorite

Labradorite, calcium-rich plagioclase feldspar (approximately (Ca,Na)(Al,Si)₄O₈)

Polished black labradorite heart

Labradorite, a calcium-rich plagioclase feldspar: approximately (Ca,Na)(Al,Si)4O8

Botryoidal chalcedony (possibly agate/geode material)

Chalcedony, microcrystalline quartz (SiO₂)

Quartz Crystal Geode / Druzy Cluster

Silicon Dioxide (SiO2)

Quartz Druze on Matrix

Silicon Dioxide (SiO2)

Ferruginous Quartz

Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions

Malachite and Cuprite on Host Rock

Cu2CO3(OH)2 (Malachite) and Cu2O (Cuprite)

Weathered iron-rich limestone or altered volcanic rock

Probable limonite/goethite-bearing calcite rock; exact identification requires testing

Weathered iron-rich stone, possibly sandstone or ironstone

Indeterminate; likely quartz-rich sandstone with iron-oxide cement, possibly hematite/goethite

Dyed Dalmatian Stone

Aplite (Alkali-feldspar granite) with Arfvedsonite

Iron-stained quartz or quartzite pebble

Quartz (SiO₂), possibly quartzite with hematite/goethite staining

Red Quartz (Hematoid Quartz)

Silicon Dioxide with Hematite inclusions (SiO2 + Fe2O3)

Pink druzy quartz (possibly quartz-bearing calcite)

Quartz, SiO₂; the pale pink coloration may reflect iron impurities or included feldspar. Exact identification is uncertain from the image alone.

Quartz Druzy on Agate (River Cobble)

Silicon Dioxide (SiO2)

Red Sandstone Pebble

Arenite (Fe2O3 enriched)

Chrysocolla-rich copper ore

Chrysocolla (hydrated copper aluminosilicate), likely with malachite and copper oxides

Polished malachite slab

Malachite, Cu₂CO₃(OH)₂; likely polished and possibly resin-stabilized

Iron-rich concretion or weathered ironstone

Limonite/goethite-rich ironstone; commonly approximated as hydrated iron oxides (FeO(OH)·nH₂O)

Quartz-rich rock fragment, possibly granite or quartzite

Primarily quartz (SiO₂), with possible feldspar and iron-oxide staining

Red Sandstone

Ferruginous Sandstone

Limonite (Ironstone)

Limonite (Hydrated iron(III) oxide-hydroxide, FeO(OH)·nH2O)

Red Sandstone

Clastic sedimentary rock (often dominated by SiO2 with Fe2O3)

Tumbled chalcedony (likely agate or jasper fragment)

Microcrystalline quartz, SiO₂ (chalcedony)

Weathered iron-rich limestone or marl

Calcitic carbonate rock with limonite/goethite and clay impurities (predominantly CaCO₃)