Not A Rock (Man Made Industrial Metal)

Sandstone (with Iron Staining)

Clastic Sedimentary Rock (primarily SiO2)

Quartz (Milky Quartz vein fragment)

Silicon Dioxide (SiO2)

Quartz (River Pebble)

Silicon Dioxide (SiO2)

Sandstone (Ferruginous)

Arenite (composed primarily of SiO2 with Fe2O3 cement)

Graphite Schist

C (Carbonaceous Schist)

Mica Schist

Mica Schist (primarily Muscovite and Biotite KAl2(AlSi3O10)(OH)2)

Basalt (Water-worn pebble)

Mafic Igneous Rock (primarily Plagioclase feldspar and Pyroxene)

Marble

Marble (metamorphosed limestone/dolostone). Predominantly composed of Calcite (CaCO3) for marble derived from limestone, or Dolomite (CaMg(CO3)2) for marble derived from dolostone.

Red Chert

Microcrystalline Quartz (SiO2)

Agate Geode

Silicon Dioxide (SiO2)

Mica Schist

Schist (Biotite/Muscovite rich)

Quartz (Water-worn pebble)

Silicon Dioxide (SiO2)

Bituminous Coal

Bituminous coal (Carbonaceous sedimentary rock)

Vesicular Rhyolite

Extrusive igneous rock (high-silica rhyolite)

Quartz Druze on Matrix

Silicon Dioxide (SiO2)

Vesicular Basalt (Scoria)

Extrusive Mafic Volcanic Rock (FeO-SiO2-MgO)

Pegmatite

Coarse-grained Igneous Rock (Granitic Pegmatite)

Polished Basalt

Basalt (Mafic volcanic rock)

Sandstone (Yellow/Tan Sandstone)

Arenite (primarily Quartz, SiO2)

Granite

Phaneritic Felsic Igneous Rock

Schist (Garnet-Mica Schist)

Garnet-Mica Schist

Quartz (Iron-stained or Rose variant)

Silicon Dioxide (SiO2)

Red Sandstone

Arenite (Fe2O3 rich)

Pumice

Pumice (Vesicular Felsic Glass)

Sandstone (Quartzose Sandstone)

Clastic sedimentary rock (primarily SiO2)

Sandstone

Arenite (SiO2 + various cementing minerals)

Chert (Flint Nobule)

Silicon Dioxide (SiO2)

Agate (Carnelian / Chalcedony)

Silicon Dioxide (SiO2)

Portable Ceramic Space Heater

Polished Acrylonitrile Butadiene Styrene (ABS) Plastic with Ceramic Heating Elements

Quartz Vein in Host Rock (clastic sediment)

Silicon Dioxide (SiO2) in matrix

Yellow Quartzite Pebble

Quartzite (primarily SiO2)

Banded Agate

Agate (Cryptocrystalline variety of Quartz, SiO2)

Agate (Common Chalcedony)

Silicon Dioxide (SiO2)

Clear Quartz (Druzy)

Crystalline Silicon Dioxide (SiO2)

Sandstone (Ferruginous)

Arenite (composed primarily of SiO2 with Fe2O3 cement)

Pumice

Pumicite / Vesicular Rhyolite

Bauxite

Bauxite (Mixture of Al(OH)3, AlO(OH), and Fe2O3)

Coal (likely Bituminous or Lignite)

Organic Sedimentary Rock (Carbonaceous)

Graphite-veined Quartzite

Meta-sedimentary Quartzite with Carbonaceous/Graphitic Inclusions (SiO2 + C)

Jasper (specifically Red Jasper or Iron-stained Chert)

Silicon dioxide (SiO2) with iron oxide inclusions

Garnetiferous Pegmatite

Pegmatite with Almandine Garnet and Muscovite

Basalt

Basalt (principally composed of pyroxene and plagioclase feldspar)