Mineral Composite

Geode half

Geode (often quartz/chalcedony based)

Black Sand (Magnetite/Heavy Mineral Concentrate)

Magnetite-rich Placers (Fe3O4)

Blue Apatite

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

Shark Tooth Fossil

Vertebrate fossilized tooth (various genera such as Carcharodon, Otodus, or Negaprion)

Granite

Phaneritic Plutonic Felsic Rock

Granitic Gneiss

Gneiss (Metamorphic Rock)

Gneiss with Quartz Veining

Gneiss (High-grade Metamorphic Rock)

Blue Apatite

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

Chakra Crystal Bracelet

Mixed Mineral Assortment

Lapis Lazuli (polished cabochon)

Lazurite-rich metamorphic rock (approx. Na6Ca2Al6Si6O24(SO4,S,Cl)2)

Lapis Lazuli

Sodium aluminum silicate with sulfur (main component: Lazurite [(Na,Ca)8(AlSiO4)6(SO4,S,Cl)2])

Bauxite

Bauxite (Al2O3·2H2O)

Hemimorphite

Hemimorphite (Zn4Si2O7(OH)2·H2O)

Yooperlite (Sodalite-bearing Syenite)

Sodalite-rich Syenite

Granite

Intrusive igneous rock

Gneiss

Gneiss

Blue Apatite

Fluorapatite (Ca5(PO4)3F)

Hematite

Iron(III) oxide (Fe2O3)

Rhodochrosite

Manganese carbonate (MnCO3)

Chrysocolla and Malachite Beads

Hydrated copper silicates (Chrysocolla) and Copper carbonate hydroxide (Malachite)

Lapis Lazuli (Low-grade)

Lapis Lazuli (Aggregate of Lazurite, Calcite, and Pyrite)

Bauxite

Bauxite (Al2O3·2H2O)

Lapis Lazuli

Lapis Lazuli (Complex aggregate mainly of Lazurite: (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)

Lapis Lazuli

Lapis Lazuli (Primary mineral: Lazurite, (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)

Lapis Lazuli

Na8[Al6Si6O24]S2 (Lazurite component), a rock composed primarily of Lazurite, Calcite, and Pyrite

Lapis Lazuli

Lazurite-rich metamorphic rock ((Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Copper Ore Specimen

Cupriferous Rock / Malachite-bearing ore

Not a geological specimen

N/A (man-made object)

Schist

Schist (various mineralogical compositions including mica, chlorite, talc, etc.)

Banded Gneiss (Variety of Gneiss)

Gneiss (specifically, a variety exhibiting prominent banding; mineral composition can vary, but often contains quartz, feldspar, mica, and amphibole)

Fossilized Gastropod / Coral

Phylum Mollusca / Cnidaria (Silicified or Calcified)

Kidney Stone

Calcium Oxalate (CaC2O4·nH2O)

Rainbow Fluorite

Fluorite (Calcium Fluoride, CaF2)

Chrysocolla on Matrix

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

Orthoclase Feldspar

Orthoclase (KAlSi3O8)

Gneiss

Gneiss

Bauxite (Iron-stained Chert / Ironstone Aggregate)

Hydrous aluminum oxide mixture (mainly Gibbsite Al(OH)3, Boehmite γ-AlO(OH), and Goethite α-Fe3+O(OH))

Bauxite

Bauxite (Al2O3·2H2O)

Bauxite (Pisolitic Bauxite)

Bauxite (mixture of Hydrous Aluminum Oxides)

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.

Lapis Lazuli

Lapis Lazuli (A complex rock primarily composed of Lazurite: (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)