Sedimentary Rock (Technically A Variety Of Chalcedony)

Sandstone (likely Arkose or Quartz Sandstone)

Arenite (SiO2 + varied clasts)

Banded Chert / Banded Jasper (likely a variety of Chert/Chalcedony)

Chert (microcrystalline quartz)

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide)

Chert

Silicon dioxide (SiO2)

Sandstone (with Lichen)

Arenite (primarily SiO2)

Chert (Quartz Variety)

Chert (mostly SiO2 / Silicon Dioxide)

Chert Nodule

Microcrystalline Silica (SiO2)

Porphyritic Basalt (Flowerstone)

Porphyritic Basalt (Mafic volcanic rock)

Geode (Unopened)

Silica Concretion / Geode (Formula: SiO2 for quartz internal contents)

Sandstone (Calcareous Sandstone)

Calcareous Sandstone (primarily SiO2 with CaCO3 cement)

Flower Agate

Silicon Dioxide (SiO2) - Variety of Chalcedony

Jasper (likely a variety of Yellow or Mustard Jasper)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (concretionary/nodular variant)

Microcrystalline Quartz (SiO2) with possible fossil or mineral inclusions

Chert (varieties include Flint or Jasper)

Chert (cryptocrystalline quartz; SiO₂)

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

Dragon Blood Jasper

Epidote with Pietersite or Red Jasper (Ca2Al2Fe3+[Si2O7][SiO4]O(OH))

Conglomerate

Conglomerative Sedimentary Rock

River Agate (Chert/Chalcedony)

Cryptocrystalline Quartz (SiO2)

Sandstone

Arenite (SiO2, often with CaCO3 or Fe2O3 cement)

Carnelian and White Quartz Bracelet

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Jasper and Quartzite mix

Silicon Dioxide (SiO2) with impurities

Petrified Wood

Silicified Wood (primarily SiO2)

Chert (Nodular)

Microcrystalline Silica (SiO2)

Chert (often called Flint or Jasper)

Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)

River Stone (River Pebbles)

Alluvial Deposit (typically Quartzite, Sandstone, or Granite clasts)

Kambaba Jasper

Rhyolite (with Stromatolite fossil inclusions)

Jasper Conglomerate (Puddingstone)

Siliceous Conglomerate (Quartz and Jasper clasts in a fine-grained matrix)

Banded Calcite (often sold as 'Travertine' or 'Mexican Onyx')

Calcium Carbonate (CaCO3)

Aquamarine (Pendant) and Jasper (Beads)

Beryllium aluminum silicate (Be3Al2Si6O18) with Chalcedony (SiO2)

Quartz on Matrix

Silicon Dioxide (SiO2)

Purple Chalcedony (likely dyed Agate)

Silicon Dioxide (SiO2)

Crazy Lace Agate

Silicon dioxide (SiO2) - a variety of banded Chalcedony (cryptocrystalline quartz)

Obsidian

Volcanic glass

Ruby

Corundum (Al2O3) with Chromium traces

Jasper

Silicon dioxide (SiO2) with impurities

Carnelian

Carnelian (Silicon Dioxide - SiO2)

Obsidian

Volcanic Glass (70-75% SiO2 with MgO and Fe3O4)

Quartz Pebble (Chert/Chalcedony variety)

Silicon Dioxide (SiO2)

Carnelian

Carnelian (Silicon Dioxide, SiO2)

Chert

Chert (Microcrystalline Silica, SiO2)

Green Chalcedony (likely Chrysoprase or Green Onyx)

Silicon Dioxide (SiO2) with trace nickel or chromium inclusions