Antropogenic (Man Made Glass Byproduct)

Olivine

(Mg,Fe)2SiO4

Shale

Argillaceous Rock

Pumice

Vesicular Rhyolite or Trachyte (High-silica volcanic glass)

Pumice

Pumice (Amorphous volcanic glass)

Clear Quartz

Silicon Dioxide (SiO2)

Olivine (Peridot)

Magnesium Iron Silicate ((Mg, Fe)2SiO4)

Diorite (possibly fine-grained variety or a related intermediate intrusive rock like a felsic gabbro or a dark granodiorite)

Diorite (Igneous rock, intrusive, intermediate composition)

Peridot

Olivine (Mg, Fe)2SiO4

Peridot

Olivine (Mg, Fe)₂SiO₄

Red Quartzite

Metamorphic Quartzite (SiO2)

Sandstone

Sandstone (clastic sedimentary rock)

Granite with Epidote

Granite, containing quartz, feldspar, and epidote

Quartzite

Quartzite (SiO2)

Quartz

Quartz (Silicon Dioxide, SiO2)

Rainbow Fluorite

Fluorite (Calcium Fluoride, CaF2)

Quartz (Small Fragment)

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Green Fluorite

Calcium Fluoride (CaF2)

Apache Tear (Obsidian)

Volcanic Glass (Amorphous Silicon Dioxide)

Quartzite

Quartzite (SiO2)

Quartz

Silicon Dioxide (SiO2)

Basalt

Extrusive Igneous Rock

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

River Pebble (Chert/Quartzite)

Microcrystalline Quartz (SiO2)

Quartz (Citrine or Iron-Stained)

Silicon Dioxide (SiO2)

River Cobble (Quartzite)

Meta-orthoquartzite

Fluorite on Matrix

Calcium Fluoride (CaF2)

Milky Quartz

Silicon Dioxide (SiO2)

Jasper

Jasper (Silicon Dioxide, SiO2)

Granite

Intrusive Igneous Rock

Pink Quartz / Rose Quartz

Silicon Dioxide (SiO2)

Quartz Vug / Druzy Quartz

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Rose Quartz

Silicon Dioxide (SiO2)

Quartz Mineral

Silicon Dioxide (SiO2)

Rose Quartz

Silicon Dioxide (SiO2)

Rose Quartz

Silicon Dioxide (SiO2)

Chert / Flint

Chert (Cryptocrystalline Quartz, SiO2)

Rose Quartz

Silicon Dioxide (SiO2)

Rose Quartz

Silicon Dioxide (SiO2)