Multiple

Piddock bored rock (likely Mudstone or Shale)

Ichnofossil (Gastrochaenolites borings) in Fine-grained Sedimentary Rock

Quartzite Cobble

Quartzite (primarily SiO2)

Lapis Lazuli (Tumbled Specimen)

Lapis Lazuli (Aggregate rock containing Lazurite: (Na,Ca)8(AlSiO4)6(SO4,S,Cl)2)

Jasper

Silicon Dioxide (SiO2) with impurities (mostly Iron Oxides)

Hag Stone

Perforated Flint or Chert (SiO2)

Crazy Lace Agate

SiO2 (Silicon Dioxide) - Chalcedony variety

Granite

Phaneritic Plutonic Rock (primarily Quartz, Feldspar, and Mica/Amphibole)

Lapis Lazuli (in Matrix)

Lazurite-bearing Metamorphic Rock (Na,Ca)8(AlSiO4)6(SO4,S,Cl)2

Quartzite Pebble

Quartzite (SiO2)

Quartzite Pebble

Quartzite (SiO2)

Quartzite Cobble

Quartzite (SiO2)

Jasper (likely Polychrome or Ocean Jasper)

Silicon Dioxide (SiO2) with impurities

Quartzite (River Cobble)

SiO2 (Quartz-rich Metamorphic Rock)

Quartzite pebble

Quartzite (SiO2)

Aragonite Star Cluster

Aragonite (Calcium Carbonate, CaCO3)

Mixed Tumbled Stones Collection

Mixed Silicates and Carbonates (Quartz, Amorphous Silica, Carbonates)

Chert with Calcite Veins

Silicon Dioxide (SiO2) with Calcium Carbonate (CaCO3) intrusions

Lapis Lazuli

Lapis Lazuli (Mineral composition: Lazurite, Calcite, Sodalite, and Pyrite)

Limonite (Iron Ore)

FeO(OH)·nH2O (Hydrated Iron Oxide)

Lapis Lazuli

Lapis Lazuli (Complex silicate rock containing Lazurite (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2, Calcite, and Pyrite)

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])

Lapis Lazuli

Na8[Al6Si6O24]n(S,Cl,SO4,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.

Lapis Lazuli

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

Lapis Lazuli

Lapis Lazuli (Mineral composition: Lazurite (Na,Ca)8(AlSiO4)6(SO4,S,Cl,OH)2, Calcite, and Pyrite)

Trilobite Fossil

Trilobita (Class), likely Phacopid or Asaphid order

Peridot (Olivine)

Magnesium Iron Silicate (Mg, Fe)2SiO4

Agate

Chalcedony (cryptocrystalline variety of Quartz, SiO2)

Agate Geode / Nodular Chalcedony

Silicon Dioxide (SiO2) with impurities

Peridot

Olivine (Magnesium Iron Silicate - (Mg, Fe)2SiO4)

Botryoidal Chalcedony Geode

Silicon Dioxide (SiO2) - Chalcedony / Cryptocrystalline Quartz

Lapis Lazuli

Na8(Al6Si6O24)S2 (Lazurite is the primary constituent mineral)

Botryoidal Chalcedony in Geode/Vug

Silicon Dioxide (SiO2)

Botryoidal Chalcedony (Agate/Chert Nodule)

Chalcedony (SiO2)

Lunar Feldspathic Breccia

Lunar Meteorite (Feldspathic Regolith Breccia)

Lapis Lazuli

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

Lapis Lazuli

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

Lapis Lazuli

Lapis Lazuli (Complex aggregate mainly of 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

Rainbow Moonstone

White Labradorite (formula: (Na,Ca)(Al,Si)4O8)

Bivalve Fossil (Internal Mold/Steinkern)

Class Bivalvia (Fossilized Mold)