Mineral Based Alloy (Anthropogenic)

Bismuth crystal

Bismuth (Bi), artificially crystallized

Silicon (Industrial Grade)

Elemental Silicon (Si)

Likely galena-bearing ore

Galena (lead sulfide, PbS), possibly with quartz or calcite gangue

Native Copper

Native Copper (Cu)

Bismuth Crystal

Bismuth (element symbol Bi, atomic number 83)

Chrysocolla in Matrix

Hydrated copper silicate - (Cu,Al)2H2Si2O5(OH)4·nH2O

Greenstone Celt (Polished Stone Axe)

Metamorphosed mafic rock (often Basalt or Diabase)

Sandstone

Arenite (SiO2-rich)

Pyrite (on Quartz/Host Rock)

Iron Sulfide (FeS₂)

Mosasaur Tooth

Mosasauridae (likely Prognathodon or Enchodus sp.)

Black tourmaline (schorl)

Schorl, NaFe²⁺₃Al₆(BO₃)₃Si₆O₁₈(OH)₄

Fossil Shark Tooth

Odontaspididae (Sand Tiger Shark family)

Green Fluorite

Calcium Fluoride (CaF2)

Basalt

Basalt (Mafic Extrusive Igneous Rock)

Green Aventurine

Aventurine Quartz (SiO2 with Fuchsite inclusions)

Conglomerate

Conglomerate (clastic sedimentary rock)

Green Gneiss or Greenschist

Chlorite/Actinolite Gneiss or Schist

Gold Nugget

Native Gold (Au)

Sandstone (with Laminations)

Clastic sedimentary rock (primarily Quartz-based)

Sandstone (Ferruginous)

Arenite with Iron Oxide cement (primarily SiO2 with Fe2O3)

Sandstone (Banded Sandstone)

Clastic Sedimentary Rock (primarily SiO2 with iron oxide impurities)

Chondrite Meteorite

Ordinary Chondrite (Fe-Ni alloy, Olivine, Pyroxene)

Rose quartz (likely)

Quartz, silicon dioxide (SiO₂), pink variety

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.

Feldspar (specifically Orthoclase)

Potassium Aluminum Silicate (KAlSi3O8)

Quartz / Quartzite

Silicon Dioxide (SiO2)

Conglomerate

Clastic sedimentary rock (Puddingstone)

Sandstone (Weathered)

Arenite (primarily SiO2)

Iron Slag

Ferrous Slag (Industrial Byproduct)

Limonite

Limonite (Hydrated iron(III) oxide-hydroxide) FeO(OH)·nH2O

Jasper

Silicon Dioxide (SiO2)

Orange chalcedony geode

Microcrystalline quartz (SiO₂), commonly called carnelian or orange agate when strongly colored

Banded Calcite (Green Onyx)

Calcium Carbonate (CaCO3)

Likely raw galena-bearing ore

Galena (PbS), possibly associated with dark sphalerite or matrix minerals

Native copper (probable copper-rich mineral specimen)

Copper, Cu; possibly mixed with cuprite, malachite, and iron-oxide alteration minerals

Red Sandstone

Arenite (with Iron Oxide / Hematite cementation)

Green fluorite crystal

Fluorite (calcium fluoride, CaF₂)

Tumbled greenish chalcedony or serpentine pebble

Likely microcrystalline quartz (chalcedony, SiO₂) or serpentine-group mineral; exact identification requires testing

Sandstone (Quartz Sandstone)

Arenite (primarily SiO2)

Silver (Native Element)

Silver (Ag) in an alloy of 90% Silver and 10% Copper

Slag (Industrial Byproduct)

Artificial silicate/iron byproduct

Bivalve Fossil

Bivalvia (Phylum Mollusca)