Tektite (Natural Glass)

Mixed Chalcedony and Jasper Bracelet (possibly 'Ocean Jasper' or similar banded variety for brown beads, and blue/grey Chalcedony for the translucent beads)

Chalcedony (SiO2), Jasper (SiO2 with impurities)

Weathered pegmatite or feldspar-rich granite fragment

Granitic pegmatite, composed mainly of potassium feldspar and quartz, with minor mica; exact identification is uncertain from the photograph

Granite pebble

Coarse-grained granitic rock, principally quartz, potassium feldspar, plagioclase feldspar, and biotite mica; likely biotite granite or weathered pegmatitic granite

Chrysoprase

Chalcedony (cryptocrystalline SiO2 variety)

Rose Quartz

Rose Quartz (SiO₂)

Amethyst-bearing quartz (likely polished or naturally fractured)

Quartz, silicon dioxide (SiO₂), purple variety colored mainly by iron-related defects

Banded Agate (variety of Chalcedony)

Agate (SiO2)

Brecciated jasper (likely red-and-cream jasper)

Jasper, an opaque microcrystalline variety of quartz; primarily cryptocrystalline SiO₂ with iron-oxide staining and possible chalcedony/quartz veining

Brecciated jasper, possibly rainforest jasper

Jasper: microcrystalline to cryptocrystalline quartz, SiO₂, commonly containing hematite, goethite, chlorite, epidote, and other iron- and manganese-bearing minerals

Emerald

Beryl (variety Emerald), Be3Al2Si6O18 with Cr and/or V

Banded gneiss, probably granitic gneiss

Foliated gneiss composed mainly of quartz (SiO₂), feldspar—orthoclase/microcline and plagioclase—and dark mica, commonly biotite K(Mg,Fe)₃AlSi₃O₁₀(F,OH)₂

BROWN GRANITE (likely 'Tan Brown' or similar)

Granite (specifically a variety rich in orthoclase feldspar, often with biotite and possibly hornblende)

Chert (or possibly Flint)

SiO2 (Silicon Dioxide)

Carnelian

Carnelian (a variety of Chalcedony, which is a microcrystalline quartz, SiO2)

Jasper

Silicon Dioxide (SiO2) - a variety of Chalcedony (Cryptocrystalline Quartz)

Carnelian

Carnelian (a variety of Chalcedony, SiO2)

Chrysoprase

Chalcedony (cryptocrystalline quartz) with nickel inclusions; SiO2

Banded Jasper (possibly "Picture Jasper")

Jasper (a microcrystalline variety of Quartz / Silicon Dioxide - SiO2)

Obsidian (likely Golden Sheen Obsidian or Rainbow Obsidian, given the subtle sheen visible on some beads)

Obsidian (volcanic glass, predominantly SiO2 with various impurities)

Carnelian

Carnelian (a variety of Chalcedony, SiO2)

Jasper (likely a variety of Brecciated Jasper or a patterned variety)

Silicon dioxide (SiO2)