Rock Identifier

Category

Metamorphic Or Igneous Alteration

Browse metamorphic or igneous alteration specimens identified by the Rock Identifier community.

Learn about Metamorphic Or Igneous Alteration in the encyclopedia

Cordierite Hornfels

Cordierite Hornfels

Migmatite

Talc-carbonate Rock

Talc-carbonate Rock

Hornblende Schist

Hornblende Schist

Epidosite

Oregon Opal

Orendite

Orthoclase

Orca Agate

Orange Opal

Peacock Ore

Orange Garnet

Hematite (Iron Ore) (Hematite (Fe2O3)) — mineral

Hematite (Iron Ore)

Hematite (Fe2O3)

Epidote (Epidote (formula: Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))) — mineral

Epidote

Epidote (formula: Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))

Hematite (Iron(III) oxide (Fe2O3)) — mineral

Hematite

Iron(III) oxide (Fe2O3)

Rose Quartz (Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese) — mineral

Rose Quartz

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

Raw Emerald (Emerald Beryl) (Beryl (Be3Al2Si6O18) with chromium/vanadium impurities) — mineral

Raw Emerald (Emerald Beryl)

Beryl (Be3Al2Si6O18) with chromium/vanadium impurities

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Epidote (Epidote (Ca2(Al, Fe)3(SiO4)3(OH))) — mineral

Epidote

Epidote (Ca2(Al, Fe)3(SiO4)3(OH))

Seraphinite (Clinochlore) (Clinochlore (Mg,Fe2+)5Al(Si3Al)O10(OH)8) — mineral

Seraphinite (Clinochlore)

Clinochlore (Mg,Fe2+)5Al(Si3Al)O10(OH)8

Hematite (Tumbled) (Iron(III) oxide (Fe2O3)) — mineral

Hematite (Tumbled)

Iron(III) oxide (Fe2O3)

Red Aventurine (Strawberry Quartz / Sunstone Quartz) (Silicon Dioxide with Hematite/Goethite inclusions (SiO2)) — mineral

Red Aventurine (Strawberry Quartz / Sunstone Quartz)

Silicon Dioxide with Hematite/Goethite inclusions (SiO2)

Emerald (Beryl (Be3Al2(SiO3)6)) — gemstone

Emerald

Beryl (Be3Al2(SiO3)6)

Orange Calcite (Calcite (CaCO3)) — Mineral

Orange Calcite

Calcite (CaCO3)

Raw Emerald in Matrix (Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities) — mineral

Raw Emerald in Matrix

Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities

Black Onyx (Silicon Dioxide (SiO2) with parallel banding) — mineral

Black Onyx

Silicon Dioxide (SiO2) with parallel banding

Bull Quartz (Milky Quartz) (Silicon Dioxide (SiO2)) — mineral

Bull Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Yellow Sapphire (Corundum (Al2O3)) — mineral

Yellow Sapphire

Corundum (Al2O3)

Cloud Quartz (Milky Quartz) (Silicon Dioxide (SiO2)) — mineral

Cloud Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Greenstone (Chert) (Microcrystalline Silica (SiO2) with chlorite/epidote inclusions) — metamorphic

Greenstone (Chert)

Microcrystalline Silica (SiO2) with chlorite/epidote inclusions

Weathered gray-green pebble (Indeterminate; possibly altered basalt, serpentinite, or a greenish metamorphic rock) — mineral

Weathered gray-green pebble

Indeterminate; possibly altered basalt, serpentinite, or a greenish metamorphic rock

Yellow Quartz (Citrine/Yellow Jasper mix) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrine/Yellow Jasper mix)

Silicon Dioxide (SiO2)

Serpentinite (likely) (Serpentinite, dominated by serpentine-group minerals (antigorite, lizardite, chrysotile), commonly with magnetite and minor chlorite/talc) — metamorphic

Serpentinite (likely)

Serpentinite, dominated by serpentine-group minerals (antigorite, lizardite, chrysotile), commonly with magnetite and minor chlorite/talc

Epidote (Epidote (Ca2(Al2,Fe3+)3(SiO4)3(OH))) — metamorphic

Epidote

Epidote (Ca2(Al2,Fe3+)3(SiO4)3(OH))

Dragon Blood Jasper (Epidote with Red Piedmontite (silicate)) — sedimentary

Dragon Blood Jasper

Epidote with Red Piedmontite (silicate)

Gold Nugget (Native Gold (Au)) — mineral

Gold Nugget

Native Gold (Au)

Nephrite Jade (Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)) — metamorphic

Nephrite Jade

Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)

Yellow Sapphire (Corundum (Al2O3:Fe)) — gemstone

Yellow Sapphire

Corundum (Al2O3:Fe)

Green Quartz / Prasiolite (Silicon Dioxide (SiO2)) — mineral

Green Quartz / Prasiolite

Silicon Dioxide (SiO2)

Serpentine (Antigorite, Lizardite, or Chrysotile (Mg, Fe)3Si2O5(OH)4) — metamorphic

Serpentine

Antigorite, Lizardite, or Chrysotile (Mg, Fe)3Si2O5(OH)4

Ruby (Pinkish-Red) (Corundum (Al2O3 with Chromium trace)) — mineral

Ruby (Pinkish-Red)

Corundum (Al2O3 with Chromium trace)

Tumbled serpentine (likely) (Serpentinite; chiefly serpentine-group minerals, Mg₃Si₂O₅(OH)₄) — metamorphic

Tumbled serpentine (likely)

Serpentinite; chiefly serpentine-group minerals, Mg₃Si₂O₅(OH)₄

Quartz Vein on Matrix (Silicon Dioxide (SiO2)) — mineral

Quartz Vein on Matrix

Silicon Dioxide (SiO2)

Blue Sapphire (Corundum (Al2O3)) — gemstone

Blue Sapphire

Corundum (Al2O3)

Porphyritic Andesite or Basalt (Porphyritic Intermediate/Mafic Igneous Rock) — igneous

Porphyritic Andesite or Basalt

Porphyritic Intermediate/Mafic Igneous Rock

Rough Gemstone Grains (Mixed Sapphires and Quartz) (Corundum (Al2O3) and Quartz (SiO2)) — mineral

Rough Gemstone Grains (Mixed Sapphires and Quartz)

Corundum (Al2O3) and Quartz (SiO2)

Gold Ore in Matrix (Native Gold (Au) in Quartz/Host Rock) — mineral

Gold Ore in Matrix

Native Gold (Au) in Quartz/Host Rock

Gold Ore (Native Gold (Au) in Matrix) — mineral

Gold Ore

Native Gold (Au) in Matrix

Chrysotile Asbestos (Mg3Si2O5(OH)4) — mineral

Chrysotile Asbestos

Mg3Si2O5(OH)4

Weathered granite (likely with accessory quartz) (Granite; chiefly quartz, K-feldspar, plagioclase, and biotite/hornblende) — igneous

Weathered granite (likely with accessory quartz)

Granite; chiefly quartz, K-feldspar, plagioclase, and biotite/hornblende

Lapis Lazuli (Lapis Lazuli (Complex rock primarily composed of Lazurite (Na,Ca)8[(SO4,S,Cl)2|(AlSiO4)6], Calcite, and Pyrite)) — metamorphic

Lapis Lazuli

Lapis Lazuli (Complex rock primarily composed of Lazurite (Na,Ca)8[(SO4,S,Cl)2|(AlSiO4)6], Calcite, and Pyrite)

Epidote (Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)) — metamorphic

Epidote

Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)

Epidote in Quartz (Epidote (Ca2(Al2,Fe3+)3(SiO4)3(OH)) / Quartz (SiO2)) — metamorphic

Epidote in Quartz

Epidote (Ca2(Al2,Fe3+)3(SiO4)3(OH)) / Quartz (SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)