Anthropogenic (Man Made Material)

Basalt

Basalt (Aphanitic Mafic Igneous Rock)

Coquina

Biogenic Limestone (Calcite, CaCO3)

Anthracite Coal

Anthracite (Carbon Content: 86%–98%)

Sodalite

Sodalite, Na8(Al6Si6O24)Cl2

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Gold (Processed)

Gold (Au)

Sandstone

Quartz Arenite (a type of sandstone composed of more than 90% quartz)

Diamond

Diamond (C)

Basalt with Scoria/Vesicular Texture

Extrusive Mafic Igneous Rock (primarily Plagioclase Feldspar and Pyroxene)

Cherry Creek Jasper (also known as Red Creek Jasper or Cherry Creek Agate)

Jasper, microcrystalline quartz (SiO₂)

Labradorite (a variety of Anorthosite or Plagioclase)

Labradorite (member of Plagioclase Feldspar series), (Ca,Na)(Al,Si)4O8

Kyanite (Blue Kyanite)

Kyanite (Al2SiO5)

Rose Quartz

Silicon Dioxide with traces of Titanium, Iron, or Manganese (SiO2)

Rose Quartz

Quartz (Silicon Dioxide - SiO2)

Turquoise

Turquoise (Hydrated phosphate of copper and aluminium) - CuAl6(PO4)4(OH)8·4H2O

Banded Chert (Flint)

Cryptocrystalline Quartz (SiO2)

Sandstone

Sandstone (lithified quartz arenite, arkose, graywacke, etc. depending on composition)

Diamond

Diamond (Carbon, C)

Jasper

Silicon Dioxide (SiO2)

Basalt

Basalt (extrusive igneous rock)

Chert (Flint)

Silicon Dioxide (SiO2)

Mica Schist

Mica Schist (predominantly composed of Muscovite or Biotite silicates)

Red Jasper

Jasper (a variety of Quartz, SiO2)

Anthracite Coal

Anthracite (Carbon-based organic sedimentary rock transitioned to metamorphic)

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.

Zebra Jasper

Silicon dioxide (SiO2) with various impurities

Diorite

Diorite

Limestone

Calcium Carbonate (CaCO3)

Banded Chert

Cryptocrystalline Quartz (SiO2)

Jasper (Imperial Jasper style)

Silicon Dioxide (SiO2) with impurities

Shale or Argillite

Shale (sedimentary) / Argillite (metamorphic)

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Greisen (Quartz-Muscovite-Turretine Rock)

Greisen

Chert (Iron-stained)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Slate

Slate (a fine-grained, foliated metamorphic rock). Mineral composition: Primarily composed of mica minerals (muscovite, chlorite, sericite) and quartz, with minor amounts of hematite, pyrite, and other accessory minerals.

Turquoise

Hydrated phosphate of copper and aluminium: CuAl6(PO4)4(OH)8·4H2O

Charoite

Charoite (Hydrated silicate of potassium, sodium, calcium, barium and strontium): (K,Sr,Ba)(Na,Ca)2[Si4O10](OH,f)·H2O

Rose Quartz

Rose Quartz (SiO₂)

Quartzite

Quartzite (primarily SiO2)

Serpentinite

Serpentinite (Mg, Fe, Ni)₃Si₂O―(OH)₄

Aquamarine

Aquamarine (Beryl variety) - Be3Al2(Si6O18)

Schist

Schist (various compositions)