Sedimentary Rock Or Mineral (Depending On Origin And Purity)

Carnelian

Chalcedony (cryptocrystalline quartz), SiO2 (Silicon Dioxide)

Riverstone Quartzite

Quartzite (primarily SiO2)

Red Siltstone (or Red Shale)

Clastic Sedimentary Rock (Composition: primarily Quartz, Clay minerals, and Hematite Fe2O3)

Graphite

Graphite (Native Carbon, C)

Gold Ore in Matrix

Native Gold (Au) in Quartz/Limonite host rock

Granite

Granite

Shale or Slate with Quartz Veins

Shale (fine-grained clastic sedimentary rock) or Slate (low-grade metamorphic rock formed from shale) with Quartz (SiO2) veins

Unakite

Unakite (Altered Granite consisting of Orthoclase KAlSi3O8, Epidote Ca2(Al,Fe)3(SiO4)3(OH), and Quartz SiO2)

Kyanite

Kyanite (Al2SiO5)

Larimar

Blue Pectolite (NaCa2Si3O8(OH))

Green Aventurine and Clear Quartz

Green Aventurine (Silicon Dioxide - SiO2 with Fuchsite inclusions); Clear Quartz (Silicon Dioxide - SiO2)

Agate (Common Chalcedony)

Silicon Dioxide (SiO2)

Lapis Lazuli

Lapis Lazuli (a rock composed primarily of Lazurite (Na,Ca)₈[(S,Cl,SO₄,OH)₂|(Al₆Si₆O₂₄)], with varying amounts of Calcite, Pyrite, and Sodalite.)

Granitic Pegmatite

Coarse-grained Granite (KAlSi3O8 + SiO2)

Yellow Quartz Pebble (Citrine or Iron-stained Quartz)

Silicon Dioxide (SiO2)

Quartzite

Metamorphosed Quartz Sandstone (SiO2)

Quartzite (Quartz-rich Cobble)

Quartzite (SiO2)

Sandstone

Arenite (Siliclastic Sedimentary Rock)

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Iron Oxide cement)

Sandstone (Banded)

Clastic Sedimentary Rock: Arenite

Sandstone

Arenite (composed primarily of SiO2)

Slate

Foliated Metamorphic Rock (composed primarily of silica and alumina with iron and magnesium)

Brecciated Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Sandstone (likely Graywacke or Lithic Sandstone)

Clastic Sedimentary Rock

Shale

Lutaceous Sedimentary Rock

Basalt Pebble

Extrusive Mafic Igneous Rock

Limestone (Fossiliferous)

Calcium Carbonate (CaCO3)

Brown Sandstone

Arenite (primarily Quartz and Feldspar, with Iron Oxide cement)

Quartz (Druzy) in host rock

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

Sandstone

Arenite (SiO2 based)

Quartz-veined Mudstone or Argillite

SiO2 (Quartz) in Siltstone/Mudstone matrix

Shungite

Shungite (carbon-rich Precambrian mineraloid)

Chert Breccia (Yellow Jasper)

Silicon Dioxide (SiO2) - Brecciated Chert

Sandstone

Arenite (primarily SiO2)

Sandstone (Ferruginous)

Arenite (SiO2 with iron oxide impurities)

Sandstone

Arenite (SiO2 principal)

Biotite (Black Mica)

Biotite - K(Mg,Fe)3AlSi3O10(F,OH)2

Sandstone

Arenite (composed primarily of SiO2)

Garnet (Red Garnet)

Garnet Group. The red varieties seen in jewelry are typically Almandine (Fe3Al2(SiO4)3), Pyrope (Mg3Al2(SiO4)3), or a mix of the two (pyrope-almandine series).

Granite

Granite (a common name for a felsic intrusive igneous rock)

Sandstone (Quartz-rich)

Arenite (primarily SiO2)

Sodalite

Sodalite (Na4Al3Si3O12Cl)