Metamorphic (Localized) Or Sedimentary

Quartz (likely macrocrystalline variety)

Quartz (SiO₂)

Quartz Geode (with Calcite influence)

Silicon Dioxide (SiO2) with possible Calcium Carbonate (CaCO3)

Black Obsidian and Hematite

Volcanic Glass (SiO2) and Hematite (Fe2O3)

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Quartz (likely) or a Quartzite Pebble

Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.

Carnelian

Carnelian (Silicon Dioxide, SiO2)

Green Jasper

Silicon Dioxide (SiO2) with mineral inclusions

Botryoidal Chalcedony

Silicon Dioxide (SiO2)

Carnelian and White Quartz Bracelet

Silicon Dioxide (SiO2) - specifically Carnelian (Chalcedony) and Rock Crystal/Snow Quartz

Quartz with Iron Stains

Quartz (SiO2) with iron oxide/hydroxide staining

Quartz Geode/Cluster

Quartz (SiO2)

Agate (Chert/Chalcedony)

Cryptocrystalline Quartz (SiO2)

Jasper with Quartz (Agate/Jasper mix)

Silicon Dioxide (SiO2) with iron oxide inclusions

Quartz Geode

Silicon Dioxide (SiO2) - Crystalline Quartz

Carnelian

Carnelian (Silicon Dioxide, SiO2)

Druzy Quartz (on Chalcedony/Agate base)

Silicon Dioxide (SiO2)

Jasper

Silicon dioxide (SiO2) with impurities

Agate / Banded Chalcedony

Agate (Silicon Dioxide / SiO2)

Carnelian

Carnelian (SiO2)

Limonite (Iron Ore/Hydrated Iron Oxide)

Limonite (mixture of FeO(OH)·nH₂O minerals, mainly Goethite, FeO(OH) and Lepidocrocite, FeO(OH))

Quartz (likely a macrocrystalline variety like milky quartz or smoky quartz, given the appearance in the image)

Quartz (SiO₂ - Silicon Dioxide)

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

Orthoclase Feldspar (or K-Feldspar)

Orthoclase (KAlSi3O8)

Epidote (or Epidote-rich rock)

Epidote. Mineral formula: Ca2(Al,Fe)3(SiO4)3(OH).

Mixed collection of Quartz varieties, Chalcedony, and metamorphic pebbles

Mixed gemstones (primarily Silicon Dioxide - SiO2)

Quartz (Rock Crystal) with minor impurities

Quartz (SiO2)

Blue Quartz

Quartz (SiO2) with inclusions

Orange Calcite

Calcite (Calcium Carbonate, CaCO3)

Quartz

Quartz (SiO₂)

Chert (Flint)

Silicon Dioxide (SiO2)

Shale or Mudstone (Based on appearance)

Shale (fine-grained, laminated fissile sedimentary rock) / Mudstone (fine-grained, non-fissile sedimentary rock)

Carnelian (Red Agate)

Silicon dioxide (SiO2) with iron oxide impurities

Yellow Chalcedony (Agate)

Silicon Dioxide (SiO2)

Tumbled Carnelian and Quartz Mix

Silicon Dioxide (SiO2) with iron oxide impurities

Carnelian

Carnelian (Silicon Dioxide - SiO2)

Leopard Skin Jasper

Jasper (Silicon Dioxide with impurities), SiO2

Jasper (Green/Dragon Blood variety)

Silicon Dioxide (SiO2) with iron/clay inclusions

Banded Gneiss (Variety of Gneiss)

Gneiss (specifically, a variety exhibiting prominent banding; mineral composition can vary, but often contains quartz, feldspar, mica, and amphibole)

Carnelian Agate

Silicon Dioxide (SiO2)

Geode (unopened nodule)

Silicon Dioxide (SiO2) Nodule

Limonite

Limonite (Hydrous iron oxides, predominantly Goethite FeO(OH)·nH2O)

Quartz Geode Fragment

Silicon Dioxide (SiO2)