Sedimentary And Metamorphic Minerals

Browse sedimentary and metamorphic minerals specimens identified by the Rock Identifier community.

Copper-bearing Mica Schist

Mica Schist with Native Copper inclusions

metamorphic

Gneiss

High-grade Metamorphic Gneiss

metamorphic

Schist

Mica Schist

metamorphic

Rough Garnet in Matrix

Almandine Garnet (Fe3Al2Si3O12)

mineral

Schist with Biotite and Quartz

Biotite-Quartz Schist (Fe,Mg,Al silicate mix)

metamorphic

Gneiss (Banded Gneiss)

Gneiss

metamorphic

Schist

Mica Schist (Variable chemistry, often rich in muscovite and biotite)

metamorphic

Banded Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

metamorphic

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

metamorphic

Green Aventurine

Quartz with Fuchsine inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)

mineral

Rhodonite

Rhodonite (Mn,Fe,Mg,Ca)SiO3

mineral

Aventurine (likely Green Aventurine)

Silicon Dioxide (SiO2) with mineral inclusions

Mineral/Mineraloid within a rock matrix

Gneiss (Metamorphic Rock)

Gneiss

metamorphic

Green Aventurine (Green Quartzite)

Silicon Dioxide (SiO2) with inclusions of Fuchsite mica

metamorphic

Amphibolite (specifically Hornblende Schist/Gneiss)

Amphibole-rich Metamorphic Rock

metamorphic

Gneiss

Gneiss (High-grade metamorphic rock)

metamorphic

Marble

Marble (metamorphosed limestone or dolostone), primarily composed of calcite (CaCO3) or dolomite (CaMg(CO3)2)

metamorphic

Gneiss Pebble

Gneiss

metamorphic

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

metamorphic

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

mineral

Gneiss

metamorphic

Pyrite

Iron Disulfide (FeS2)

mineral

Hematite

Iron(III) oxide (Fe2O3)

mineral

Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

metamorphic

Gneiss (specifically a Banded Gneiss cobble)

Gneiss (composed mainly of Quartz, Feldspar, and Biotite/Amphibole)

metamorphic

Beaded Jewelry (Assorted Gemstones)

Various minerals, including but not limited to Quartz (SiO2), Garnet (X3Y2(SiO4)3), Jade (Na(Al,Fe)Si2O6), Amethyst (SiO2),等の多様な組み合わせ

Mineral, Jewelry

Gneiss

Gneiss (High-grade metamorphic rock)

metamorphic

Rough Garnet (Almandine)

Almandine Garnet (Fe3Al2(SiO4)3)

mineral

Epidote

{Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)

mineral

Blue Calcite

Calcite (CaCO3)

mineral

Given the appearance, it's likely a fragment of an igneous or metamorphic rock composed of multiple minerals. Without specific diagnostic features, it's difficult to give a common name other than 'crystalline rock fragment'. If pressed to guess based on the granular, somewhat light and dark speckled appearance, it could be a fragment of granite or a related intrusive igneous rock.

As a rock fragment, it does not have a single scientific mineral name; rather, it's a piece of a rock which is a combination of minerals. If it were granite, its main mineral composition would be quartz (SiO2), feldspar (e.g., KAlSi3O8 - orthoclase, (Na,Ca)(Al,Si)4O8 - plagioclase), and mica (e.g., KAl2(AlSi3O10)(OH)2 - muscovite or K(Mg,Fe)3AlSi3O10(OH)2 - biotite), among others.

Mineral, possibly rock fragment containing a mineral