This Appears To Be A Man Made Metallic Object, Likely Jewelry, Not A Natural Rock, Mineral, Or Geological Specimen.

Blue Lace Agate (Heat-treated/Crackle Quartz variety)

Silicon Dioxide (SiO2)

Mineral, possibly rock fragment containing a mineral

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.

Quartz

Quartz (SiO₂ - Silicon Dioxide)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Nephrite (a form of Jade)

Nephrite (a variety of the mineral actinolite, Ca2(Mg,Fe)5Si8O22(OH)2)

Gold Ore in Quartz

Auriferous Quartz (Gold: Au; Quartz: SiO2)

Smoky Quartz

Smoky Quartz (SiO2)

Gold Nugget (Placer Gold)

Native Gold (Au)

Specular Hematite (Specularite)

Iron Oxide (Fe2O3)

Basalt (Weathered Pebble)

Extrusive mafic igneous rock; minerals primarily Plagioclase feldspar and Pyroxene

Chert (Nodule/Pebble)

Chert (Silicon Dioxide, SiO2)

sedimentary

Pink Dyed Agate

Silicon Dioxide (SiO2) - Variety Agate

Amber (Copal)

Organic gemstone, fossilized tree resin (often immature amber or copal)

Purple Dyed Agate Geode (Banded Chalcedony)

Silicon Dioxide (SiO2) - variety: Agate

Granite

Granite (a plutonic rock)

Igneous

Milky Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon dioxide (SiO2)

Obsidian

Obsidian (volcanic glass, amorphous silica rich rock)

Igneous

Pink Chalcedony (Agate/Jasper blend)

Silicon Dioxide (SiO₂)

Silver (Native or Alloyed)

Ag (Argentum)

Black Opal

Hydrated Amorphous Silica (SiO2·nH2O)

Gold in Quartz

Hydrothermal Quartz with Native Gold (SiO2 with Au)

Pyrite in Shale

Iron Disulfide (FeS2)

Petrified Wood (Silicified Wood)

Silicified Wood (primarily Chalcedony/Quartz, SiO2)

Amazonite

Amazonite (KAlSi3O8 - Microcline)

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Amazonite

Potassium Feldspar (Microcline) - KAlSi3O8

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

metamorphic

Basalt

Basalt (Mafic volcanic rock)

Basalt with Iron Oxidation (Lattice/Veined)

Mafic Volcanic Rock (principally Plagioclase and Pyroxene)

Phantom Quartz with Chlorite and Hematite inclusions

Silicon Dioxide (SiO2) with inclusions of Chlorite group minerals and Hematite (Fe2O3)

Smoky Quartz

Silicon Dioxide (SiO2)

River Quartzite Siltstone

Quartz-rich Meta-siltstone (SiO2 dominated)

metamorphic

Petrified Wood

Silicified Wood (SiO2)

K2 Jasper (Beads)

Granodiorite with Azurite and Malachite

Calcite

Calcite (CaCO3)

Aventurine (Green Aventurine)

Quartz with Fuchsite Inclusions (SiO2)

Yellow Quartz (Chalcedony or Agate)

Silicon Dioxide (SiO2)

Quartz Crystal (specifically a Double-Terminated variety)

Silicon Dioxide (SiO2) - Low Quartz

Fluorite

Calcium Fluoride (CaF2)