Mineral (Found In Igneous And Metamorphic Rocks)

Unakite or Epidosite

Epidosite (Mineral composition: Epidote, Feldspar, and Quartz)

Banded Gneiss

Gneiss (High-grade Metamorphic Rock)

Moonstone (Tumbled)

Orthoclase Feldspar (KAlSi3O8) with inclusions of Albite

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.

Sodalite

Na8(Al6Si6O24)Cl2 (Sodalite)

Ruby

Corundum (Aluminum Oxide with Chromium traces), Al2O3:Cr

Red Garnet

Pyrope-Almandine series (Mg3Al2(SiO4)3 to Fe3Al2(SiO4)3)

Greenschist

Greenschist (Actinolite-Chlorite Schist)

Citrine

Silicon Dioxide (SiO2) with iron impurities

Limonite-stained Quartz

Silicon Dioxide (SiO2) with Iron Oxide/Hydroxide (FeO(OH)·nH2O) staining

Gneiss

Gneiss

Magnetite with Pyrite or Chalcopyrite inclusions

Magnetite (Fe3O4) with Pyrite (FeS2)

Gneiss

Gneiss (High-grade metamorphic rock)

Gneiss

Foliated Metamorphic Rock (Gneiss)

Quartz (Milky/Chalcedony variety)

Silicon Dioxide (SiO2)

Yellow Agate

Silicon Dioxide (SiO2)

Parti Sapphire

Corundum (Al2O3)

Green Quartz (Aventurine)

Silicon Dioxide with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)

Rutilated Quartz (likely Citrine or Smoky Quartz with Rutile inclusions)

SiO2 with TiO2 inclusions (Quartz with Rutile)

Quartz Vein / Milky Quartz

Silicon Dioxide (SiO2)

Muscovite (Mica) in Quartz Matrix

Muscovite (KAl2(AlSi3O10)(OH)2) and Quartz (SiO2)

Green Aventurine

Silicon dioxide (SiO2) with inclusions of Fuchsite

Orthoclase Feldspar

Orthoclase (KAlSi3O8)

Quartz / Rock Crystal

Silicon Dioxide (SiO2)

White Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Gneiss

Gneiss (High-grade Metamorphic Rock)

Greenschist (Greenstone River Pebble)

Greenschist (Chlorite Schist)

Quartz (Milky or Smoky Quartz)

Silicon Dioxide (SiO2)

Black Tourmaline

Schorl (Sodium Iron Aluminum Borosilicate Hydroxide), NaFe3Al6(BO3)3Si6O18(OH)4

Quartz

Quartz (Silicon Dioxide, SiO2)

Gneiss

Gneiss

Pyrite on Quartz

Iron Sulfide (FeS2) on Silicon Dioxide (SiO2)

Quartz (Rock Crystal)

Quartz (SiO₂ - Silicon Dioxide)

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Smoky Quartz

Smoky Quartz (Silicon Dioxide - SiO2)

Epidote

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

Granitic Pegmatite (Muscovite and Quartz)

Pegmatite (KAl2(AlSi3O10)(OH)2 / SiO2)

Quartz River Cobble

Silicon Dioxide (SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Smoky Quartz (Tumbled)

Silicon Dioxide (SiO2)

Clear Quartz Crystal

Silicon Dioxide (SiO2)

Graphite

Graphite (Carbon, C)