Metamorphic Mineral

Gneiss

Metamorphic Gneiss (High-grade regional metamorphism)

Schist

Mica Schist

Muscovite Mica

Muscovite (Potassium Aluminum Silicate) - KAl2(AlSi3O10)(F,OH)2

Black Sand (Magnetite Sand)

Magnetite (Fe3O4)

Hypersthene

Hypersthene ((Mg,Fe)SiO₃)

Orthoclase Feldspar

Orthoclase (KAlSi3O8)

Tumbled Moonstone

Feldspar (Orthoclase/Albite), KAlSi3O8

Chalcopyrite

Copper Iron Sulfide (CuFeS2)

Magnetic Sand Grain / Magnetite Pellet

Magnetite (Fe3O4)

Serpentinite

Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4

Mixed Mineral and Fossil Collection

Multi-specimen assemblage (SiO2, CaCO3, FeS2, etc.)

River Stone (possibly Gneiss)

Metamorphic Gneiss

Mica (Biotite or Phlogopite variety)

Phyllosilicate (complex mineral formula involving K, Mg, Fe, Al, Si, and O)

Almandine Garnet in Schist

Almandine, Fe3Al2(SiO4)3

Banded Gneiss

Gneiss (Metamorphic Rock)

Gneiss

Metamorphic Gneiss (High-grade regional metamorphism)

Greenish Metamorphic Rock (likely containing epidote or chlorite)

Metamorphic rock, possibly epidosite or greenstone

Fuchsite

Chromium-rich Muscovite (KAl2(AlSi3O10)(OH,F)2 with Cr replacements)

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

Pyrite

Iron Sulfide (FeS2)

Prehnite

Prehnite (Ca2Al(AlSi3O10)(OH)2)

Jade

There are two distinct minerals commonly known as Jade: Nephrite (a calcium magnesium silicate - Ca2(Mg,Fe)5Si8O22(OH)2) and Jadeite (a sodium aluminum silicate - NaAlSi2O6). Based on the image showing a typically softer, more fibrous appearance, it is likely Nephrite.

Mica Schist

Mica Schist (predominantly Muscovite or Biotite sheet silicates)

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

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.

Green Aventurine

Aventurine Quartz (SiO2 + Fuchsite inclusions)

Amazonite

Microcline (K(AlSi3O8))

Tiger's Eye

Silicon Dioxide (SiO2) with fibrous inclusions

Yellow Calcite

Calcium Carbonate (CaCO3)

Aventurine

Silicon Dioxide (SiO2) with Fuchsite inclusions

Grey River Stone (Gneiss/Schist mix)

Foliated Metamorphic Rock (variable mineral formula)

Yellow Aventurine (Yellow Quartzite)

Silicon Dioxide (SiO2) with inclusions

Fuchsite

Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)

Rhodonite

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

Epidote

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

Green Aventurine

Aventurine Quartz (SiO2 + Fuchsite mica)

Blue Apatite

Apatite, Ca5(PO4)3(F,Cl,OH)

Quartz Vein in Pelite (Metamorphic Rock)

Hydrothermal Quartz Veining in Metasedimentary Rock (SiO2)

Quartz with Muscovite Mica

Silicon Dioxide (SiO2) with Potassium Aluminum Silicate Hydroxide Fluoride (KAl2(AlSi3O10)(F,OH)2)

Prehnite

Ca2Al(AlSi3O10)(OH)2

Quartz Heart or Arrowhead Shape

Silicon Dioxide (SiO2)

Rhodonite

Rhodonite (MnSiO3)