Quartz with Iron Oxide Monzonite or Sandstone contact rock specimen

Quartz with Iron Oxide Monzonite or Sandstone contact

Quartz (SiO2) with Limonite/Hematite staining

mineral

Quartz / Common Agate rock specimen

Quartz / Common Agate

Silicon Dioxide (SiO2)

mineral

Unakite (Epidotized Granite) rock specimen

Unakite (Epidotized Granite)

Epidotized Granite (SiO2 with Ca2(Al,Fe)3(SiO4)3(OH))

metamorphic

Chert (Iron-stained) rock specimen

Chert (Iron-stained)

Silicon Dioxide (SiO2)

sedimentary

Red Quartzite / Ferruginous Quartzite rock specimen

Red Quartzite / Ferruginous Quartzite

Quartzite (primarily SiO2 with Fe2O3 inclusions)

metamorphic

Chert (Flint) rock specimen

Chert (Flint)

Silicon Dioxide (SiO2)

sedimentary

River Pebble (Quartzite/Sandstone mix) rock specimen

River Pebble (Quartzite/Sandstone mix)

Quartzite (primarily SiO2)

metamorphic

Quartzite River Rock (with Limonite staining) rock specimen

Quartzite River Rock (with Limonite staining)

Quartzite (SiO2)

metamorphic

Quartzite rock specimen

Quartzite

Quartzite (primarily SiO2)

metamorphic

Petrified Wood rock specimen

Petrified Wood

Silicified Wood (SiO2)

sedimentary

Granite rock specimen

Granite

Phaneritic Igneous Rock (Granite)

igneous

Petrified Wood rock specimen

Petrified Wood

Silicified Wood (SiO2 permineralization)

sedimentary

Petrified Wood rock specimen

Petrified Wood

Silicified Wood (SiO2)

mineral

Sandstone (Water-worn) rock specimen

Sandstone (Water-worn)

Arenite

sedimentary

Chert (Common Opal/Chalcedony mixture) rock specimen

Chert (Common Opal/Chalcedony mixture)

Silicon Dioxide (SiO2)

sedimentary

Petrified Wood rock specimen

Petrified Wood

Silicified Wood (SiO2)

sedimentary

Petrified Wood rock specimen

Petrified Wood

Silicified Wood (SiO2)

sedimentary

Milky Quartz with Iron Staining rock specimen

Milky Quartz with Iron Staining

Silicon Dioxide (SiO2)

mineral

Chert (Jasper/Chalcedony variety) rock specimen

Chert (Jasper/Chalcedony variety)

Silicon Dioxide (SiO2)

sedimentary

Petrified Wood rock specimen

Petrified Wood

Silicified Wood (SiO2)

sedimentary

Amethyst (Quartz) rock specimen

Amethyst (Quartz)

Amethyst (SiO2 with iron impurities)

mineral

Rose Quartz rock specimen

Rose Quartz

Silicon dioxide (SiO2) with trace amounts of titanium, iron, or manganese

mineral

Prehnite rock specimen

Prehnite

Prehnite (Ca2Al(AlSi3O10)(OH)2)

mineral

Blue Chalcedony rock specimen

Blue Chalcedony

Chalcedony (SiO2)

mineral

Rhodonite rock specimen

Rhodonite

Manganese Silicate (Mn,Fe,Mg,Ca)SiO3

mineral

Graphite rock specimen

Graphite

Graphite (Native Carbon, C)

metamorphic

Anthracite Coal rock specimen

Anthracite Coal

Low-grade metamorphic carbonaceous rock

metamorphic

Botryoidal Goethite rock specimen

Botryoidal Goethite

Goethite (α-Fe3+O(OH))

mineral

Labradorite rock specimen

Labradorite

Labradorite (Plagioclase Feldspar Series: (Ca,Na)(Al,Si)4O8)

mineral

Quartzite Pebble rock specimen

Quartzite Pebble

Metamorphic Quartz (SiO2)

metamorphic

Jasper rock specimen

Jasper

Jasper (Silicon Dioxide, SiO2 with iron inclusions)

sedimentary

Chert (specifically Flint or Common Chert) rock specimen

Chert (specifically Flint or Common Chert)

Silicon Dioxide (SiO2)

sedimentary

Quartz (Milky/Clear Quartz) rock specimen

Quartz (Milky/Clear Quartz)

Silicon Dioxide (SiO2)

mineral

Quartz (Milky Quartz) rock specimen

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

mineral

Yellow Quartzite (River Pebble) rock specimen

Yellow Quartzite (River Pebble)

Silicon Dioxide (Metamorphosed Sandstone), SiO2

metamorphic

Yellow Quartzite (River Stone) rock specimen

Yellow Quartzite (River Stone)

Quartzite (primarily SiO2)

metamorphic

Quartzite rock specimen

Quartzite

Quartzite (primarily SiO2)

metamorphic

Quartzite rock specimen

Quartzite

Quartzite (primarily SiO2)

metamorphic

Tiger's Eye (Rough) rock specimen

Tiger's Eye (Rough)

Pseudomorph of Quartz after Crocidolite (SiO2 with FeOOH inclusions)

metamorphic

Jasper (Yellow Jasper) rock specimen

Jasper (Yellow Jasper)

Silicon Dioxide (SiO2) with iron inclusions

sedimentary

Amber rock specimen

Amber

Succinite

mineraloid

Yellow Quartzite (or Quartz River Pebble) rock specimen

Yellow Quartzite (or Quartz River Pebble)

Silicon Dioxide (SiO2)

metamorphic