Anthropogenic (Man Made Material Processed By Nature)

Ferruginous Breccia

Breccia with Iron-rich (Hematite/Goethite) Matrix

Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Slate

Slate (Metamorphic Rock)

Banded Gneiss

Gneiss (High-grade metamorphic rock)

Quartz

Silicon Dioxide (SiO₂)

Serpentinite

Serpentinite (composed primarily of Serpentine group minerals, (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)

Nephrite Jade (Pounamu)

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

Banded Onyx (Mexican Onyx / Travertine)

Calcite (CaCO3) - Banded Travertine

Synthetic Wolf Plush (Non-mineral)

Canis lupus similis (Prop material: Polyester & Synthetic fibers)

Red Jasper

Jasper (a variety of Chalcedony, SiO₂)

Sandstone (Quartzose)

Arenite (composed primarily of SiO2)

Quartz (Milky or Cloudy variety)

Silicon Dioxide (SiO2)

Jasper (specifically Fancy or Polychrome Jasper)

Silicon Dioxide (SiO2) - Chalcedony

Quartz

Quartz (SiO2, Silicon Dioxide)

Green Calcite

Calcite (Calcium Carbonate, CaCO3)

Blue Calcite

Calcite (Calcium Carbonate, CaCO3)

Red Jasper

Jasper (Silicon Dioxide, SiO2)

Mica Schist

Mica Schist (Complex Silicate Rock)

Travertine (often colloquially called Tufa)

Chemical Sedimentary Calcium Carbonate (CaCO3)

Pyrite in Quartz

Iron Sulfide (FeS2) in Silicon Dioxide (SiO2)

Serpentinite

Serpentinite (complex of lizardite, chrysotile, and antigorite: (Mg,Fe)3Si2O5(OH)4)

White Jade (Nephrite)

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

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

Diamond

Carbon (C), specifically a solid form of the element carbon with atoms arranged in a crystal structure called diamond cubic.

Green Slag Glass (Cullet)

Amorphous Silica (Industrial Glass Byproduct)

Petrified Wood

Silicified wood (primarily Silicon Dioxide - SiO2)

Black Tourmaline (Schorl)

Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)

Soapstone

Steatite (primarily composed of Talc, Mg₃Si₄O₁₀(OH)₂)

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.

Petrified Wood

Silicified wood (primarily SiO2)

Mahogany Obsidian

Volcanic Glass with Hematite/Magnetite inclusions (SiO2 + Fe2O3)

Granite

Granite (a common igneous rock)

Quartz (chalcedony variety) or Limestone with Quartz Veins

SiO2 (for Quartz/Chalcedony); CaCO3 (for Limestone)

Jasper

Chalcedony (cryptocrystalline quartz), SiO2

Serpentinite (Serpentine Rock)

Primarily composed of serpentine group minerals, such as antigorite, chrysotile, and lizardite. Chemical formula for serpentine minerals is (Mg,Fe)3Si2O5(OH)4.

Quartz in Matrix (possibly Basalt or Siltstone host)

Silicon Dioxide (SiO2) in Host Rock

Grey Slate

Foliated Metamorphic Rock (formed by low-grade regional metamorphism of shale or mudstone)

Chert (Commonly known as Flint)

Microcrystalline Quartz (SiO2)

Chalcedony Geode

Chalcedony (SiO2) within a geode structure

Ferruginous Sandstone (Ironstone)

Arenite with Limonite/Goethite cement

Tektite (likely Australite)

Tektite (no specific chemical formula as it's a natural glass of variable composition, mostly SiO2, Al2O3, FeO, MgO, CaO, K2O, Na2O, TiO2)

Quartz (likely Milky Quartz)

Quartz (SiO₂ - Silicon Dioxide)