Metamorphic Rock (Primarily Composed Of Minerals)

Sandstone

Arenite (composed primarily of SiO2)

Sandstone

Arenite (primarily Quartz Arenite)

Lapis Lazuli

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

Lapis Lazuli

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

Lapis Lazuli

Lapis Lazuli (Rock composed primarily of Lazurite (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2, Calcite, and Pyrite)

Lapis Lazuli

Lapis Lazuli (Complex aggregate mainly of Lazurite: (Na,Ca)8(AlSiO4)6(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

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

Dalmatian Stone

Peralkaline Feldsphathic Igneous Rock

Granite Core Sample

Granite

Sandstone

Arenite (primarily SiO2)

Lapis Lazuli (Tumbled)

Lazurite-dominated contact metamorphic rock

Lapis Lazuli

Lapis Lazuli (Metamorphic rock primarily composed of Lazurite, Calcite, and Pyrite)

Marble

Metamorphic Limestone (CaCO3)

Lapis Lazuli

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

Granite Pebble

Phaneritic intrusive igneous rock

Green Schist

Greenschist (composed of Chlorite, Actinolite, and Epidote)

Lapis Lazuli

Na8[Al6Si6O24]Sn (Lazurite-rich metamorphic rock)

Likely amphibolite

Amphibolite, composed chiefly of hornblende and plagioclase feldspar

Greenstone / Greenschist

Greenschist facies metamorphic rock (composed primarily of chlorite, actinolite, and epidote)

Sandstone

Arenite (primarily SiO2 - Silicon Dioxide)

Chakra Crystal Bracelet

Mixed Mineral Assortment

Sandstone

Arenite (primarily SiO2 with various cementing agents)

Gneiss (specifically a Granitic Gneiss)

Gneiss (typically composed of Quartz, Feldspar, and Mica/Amphiboles)

Chalk (or Soapstone Marking Stick)

Calcium Carbonate (CaCO3) / Hydrous Magnesium Silicate (Mg3Si4O10(OH)2)

Granite / Gneiss (Felsic Metamorphic or Igneous Rock)

Gneiss (or weathered Granite)

Lapis Lazuli

Lazurite (primary mineral component), (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2

Slate

Foliated Metamorphic Rock (composed primarily of Quartz, Muscovite, and Illite)

Granite

Granite (Felsic Plutonic Rock)

Unakite

Epidotized Granite

Granite

Granite (Phaneritic intrusive igneous rock)

Gneiss

Gneiss (Metamorphic rock composed primarily of quartz, feldspar, and mica)

Aventurine

Silicon Dioxide (SiO2) with inclusions

Gneiss (Stream-worn Cobble)

Gneiss (Metamorphic rock composed primarily of Quartz, Feldspar, and Mica)

Greenstone

Metabasalt (composed of chlorite, epidote, and actinolite)

Andesite

Intermediate Volcanic Rock (Andesite)

Granite Pebble

Granite (Phaneritic Quartz-Feldspar Rock)

Sandstone

Arenite (Sedimentary rock composed of sand-sized grains)

Lapis Lazuli

Lapis Lazuli (Rock composed mainly of lazurite, calcite, and pyrite)

Slate

Slate (foliated metamorphic rock, primarily composed of quartz, illite, chlorite, and micas)

Greenstone / Serpentinite

Serpentinite (composed primarily of serpentine minerals: Mg3Si2O5(OH)4)

Likely serpentinite (greenstone pebble)

Serpentinite, composed mainly of serpentine-group minerals (e.g., lizardite, chrysotile, or antigorite)