Rock Identifier

Category

Sedimentary (Alluvial Deposit)

Browse sedimentary (alluvial deposit) specimens identified by the Rock Identifier community.

Hematite (Hematite (Fe2O3)) — Mineral

Hematite

Hematite (Fe2O3)

Quartz (Rock Crystal) (Quartz (SiO₂ - Silicon Dioxide)) — Mineral

Quartz (Rock Crystal)

Quartz (SiO₂ - Silicon Dioxide)

Muscovite Mica (Muscovite (KAl₂(AlSi₃O₁₀)(F,OH)₂))) — Mineral

Muscovite Mica

Muscovite (KAl₂(AlSi₃O₁₀)(F,OH)₂))

Red Swirl Beads (Likely Resin or Glass, simulating Red Jasper or Agate) (N/A (for the beads as pictured); Red Jasper: SiO2 (Chert variety); Red Agate: SiO2 (Chalcedony variety)) — Organic (if resin) or Synthetic (if glass); simulating Sedimentary or Metamorphic (for natural stones)

Red Swirl Beads (Likely Resin or Glass, simulating Red Jasper or Agate)

N/A (for the beads as pictured); Red Jasper: SiO2 (Chert variety); Red Agate: SiO2 (Chalcedony variety)

Organic (if resin) or Synthetic (if glass); simulating Sedimentary or Metamorphic (for natural stones)

Graphite (Graphite (Carbon, C)) — Mineral

Graphite

Graphite (Carbon, C)

Micaceous Sandstone or Quartzite (Sandstone (lithified quartz grains, often with mica) or Quartzite (metamorphosed sandstone)) — Sedimentary or Metamorphic

Micaceous Sandstone or Quartzite

Sandstone (lithified quartz grains, often with mica) or Quartzite (metamorphosed sandstone)

Sedimentary or Metamorphic

Fluorite and Rose Quartz (Fluorite (CaF2), Rose Quartz (SiO2)) — Mineral

Fluorite and Rose Quartz

Fluorite (CaF2), Rose Quartz (SiO2)

Brecciated Jasper (Silicon Dioxide (SiO2) with varying mineral inclusions (Iron Oxide, Hematite, Clay)) — sedimentary (clastic/chemical)

Brecciated Jasper

Silicon Dioxide (SiO2) with varying mineral inclusions (Iron Oxide, Hematite, Clay)

sedimentary (clastic/chemical)

Ocean Jasper (Orbicular Jasper) (Silicon Dioxide (SiO2) with various inclusions) — sedimentary (geologically classified as a variety of chalcedony/quartz)

Ocean Jasper (Orbicular Jasper)

Silicon Dioxide (SiO2) with various inclusions

sedimentary (geologically classified as a variety of chalcedony/quartz)

Green Aventurine (Aventurine (Silicon dioxide, SiO₂)) — Mineral; variety of Quartz

Green Aventurine

Aventurine (Silicon dioxide, SiO₂)

Mineral; variety of Quartz

Red Jasper (Jasper (a variety of Chalcedony, SiO₂ with impurities)) — Mineral

Red Jasper

Jasper (a variety of Chalcedony, SiO₂ with impurities)

Aragonite (variety 'Flos Ferri') (Aragonite (CaCO3)) — Mineral

Aragonite (variety 'Flos Ferri')

Aragonite (CaCO3)

Chalcedony (Chalcedony (SiO₂)) — Mineral

Chalcedony

Chalcedony (SiO₂)

Kyanite (Kyanite (Al2SiO5)) — Mineral

Kyanite

Kyanite (Al2SiO5)

Ocean Jasper (Orbicular Jasper) (Silicon Dioxide (SiO2)) — Sedimentary Rock

Ocean Jasper (Orbicular Jasper)

Silicon Dioxide (SiO2)

Sedimentary Rock

Carnelian (Chalcedony variety) (SiO2 (Silicon Dioxide)) — Mineral

Carnelian (Chalcedony variety)

SiO2 (Silicon Dioxide)

Calcite (likely a tumbled specimen) (Calcite (CaCO
3
)) — Mineral

Calcite (likely a tumbled specimen)

Calcite (CaCO 3 )

Carnelian (Chalcedony (cryptocrystalline quartz), SiO2) — Mineral

Carnelian

Chalcedony (cryptocrystalline quartz), SiO2

Quartz (likely) or a Quartzite Pebble (Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.) — Mineral, specifically a detrital grain

Quartz (likely) or a Quartzite Pebble

Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.

Mineral, specifically a detrital grain

Pyrite (Pyrite (FeS2)) — Mineral

Pyrite

Pyrite (FeS2)

Cobaltoan Calcite / Pink Dolomite (Possible) (Cobaltoan Calcite: (Ca,Co)CO3; Pink Dolomite (or Thulite): CaMg(CO3)2 or Mn-Dolomite / (Thulite: Mn2+3Al2(Si2O7)(SiO4)O(OH))) — Mineral / Rock (depending on purity)

Cobaltoan Calcite / Pink Dolomite (Possible)

Cobaltoan Calcite: (Ca,Co)CO3; Pink Dolomite (or Thulite): CaMg(CO3)2 or Mn-Dolomite / (Thulite: Mn2+3Al2(Si2O7)(SiO4)O(OH))

Mineral / Rock (depending on purity)

Amber (Amber (Fossilized Tree Resin)) — Mineral

Amber

Amber (Fossilized Tree Resin)

Mother of Pearl (Nacre) (Calcium Carbonate (primarily aragonite, with conchiolin)) — Organic Gemstone/Biomineral

Mother of Pearl (Nacre)

Calcium Carbonate (primarily aragonite, with conchiolin)

Organic Gemstone/Biomineral

Quartz Geode/Druzy Quartz (Quartz (SiO₂)) — Mineral

Quartz Geode/Druzy Quartz

Quartz (SiO₂)

Amber ((C10H16O)n – an amorphous organic substance, primarily composed of polymerized isoprenoids.) — Mineral

Amber

(C10H16O)n – an amorphous organic substance, primarily composed of polymerized isoprenoids.

Amber (Copal) (Organic gemstone, fossilized tree resin (often immature amber or copal)) — Mineral

Amber (Copal)

Organic gemstone, fossilized tree resin (often immature amber or copal)

Red Jasper (Red Jasper (variety of Chalcedony, SiO₂)) — Mineral

Red Jasper

Red Jasper (variety of Chalcedony, SiO₂)

Banded Gneiss (River Rock/Pebble) (Gneiss (specifically a banded variety often found as a river rock)) — Metamorphic Rock

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Metamorphic Rock

Mica (likely Muscovite) (Muscovite / KAl2(AlSi3O10)(OH)2) — mineral

Mica (likely Muscovite)

Muscovite / KAl2(AlSi3O10)(OH)2

Quartz (Quartz (Silicon Dioxide, SiO2)) — Mineral

Quartz

Quartz (Silicon Dioxide, SiO2)

Quartz (Quartz (SiO2 - Silicon Dioxide)) — Mineral, often found as detrital grains in sedimentary rocks

Quartz

Quartz (SiO2 - Silicon Dioxide)

Mineral, often found as detrital grains in sedimentary rocks

Clear Quartz (beads in a bracelet) (Quartz (SiO2)) — Mineral

Clear Quartz (beads in a bracelet)

Quartz (SiO2)

Fossilized Wood (Petrified Wood) (Silicified Wood (primarily quartz/chalcedony replacing organic matter)) — Sedimentary (with some aspects of mineral replacement)

Fossilized Wood (Petrified Wood)

Silicified Wood (primarily quartz/chalcedony replacing organic matter)

Sedimentary (with some aspects of mineral replacement)

Peridot and Citrine Gemstones (in a ring setting) (Peridot (Olivine: (Mg,Fe)2SiO4), Citrine (Quartz: SiO2)) — mineral

Peridot and Citrine Gemstones (in a ring setting)

Peridot (Olivine: (Mg,Fe)2SiO4), Citrine (Quartz: SiO2)

Blue Agate (Dyed) (Silicon Dioxide (SiO2)) — Sedimentary (formed from silica deposits)

Blue Agate (Dyed)

Silicon Dioxide (SiO2)

Sedimentary (formed from silica deposits)

Banded Iron Formation (Banded Iron Formation (BIF)) — Sedimentary Rock

Banded Iron Formation

Banded Iron Formation (BIF)

Sedimentary Rock

Amethyst and Limestone (Amethyst (SiO2 - Silicon Dioxide) and Limestone (CaCO3 - Calcium Carbonate)) — The purple specimen is a mineral (Amethyst); the white specimen is a sedimentary rock (Limestone or Marble).

Amethyst and Limestone

Amethyst (SiO2 - Silicon Dioxide) and Limestone (CaCO3 - Calcium Carbonate)

The purple specimen is a mineral (Amethyst); the white specimen is a sedimentary rock (Limestone or Marble).

Quartz (Silicon dioxide (SiO₂)) — Mineral

Quartz

Silicon dioxide (SiO₂)

Sandstone (with possibly iron oxides and other minerals) (Sandstone) — Sedimentary rock

Sandstone (with possibly iron oxides and other minerals)

Sandstone

Sedimentary rock

Red Jasper (Jasper (a variety of Chalcedony, SiO₂ with iron oxide inclusions)) — Mineral

Red Jasper

Jasper (a variety of Chalcedony, SiO₂ with iron oxide inclusions)

Muscovite Mica (Muscovite (Potassium Mica) KAl2(AlSi3O10)(OH)2) — Mineral

Muscovite Mica

Muscovite (Potassium Mica) KAl2(AlSi3O10)(OH)2

Onyx Marble (also commonly called Onyx) (Calcite (CaCO3), often with other mineral impurities) — Sedimentary Rock (specifically a type of Travertine)

Onyx Marble (also commonly called Onyx)

Calcite (CaCO3), often with other mineral impurities

Sedimentary Rock (specifically a type of Travertine)