Sedimentary (Base), Then Artificial

Citrine Quartz

Silicon Dioxide (SiO2)

Raw Citrine

Citrine (Silicon Dioxide, SiO2)

Yellow Topaz (Imperial or Precious Topaz)

Al2SiO4(F,OH)2 (Aluminum Silicate Fluoride Hydroxide)

Granitic Pegmatite

Granite Pegmatite (coarse-grained intrusive igneous rock)

Mahogany Obsidian

Volcanic Glass with Hematite/Magnetite inclusions (SiO2)

Marble

Recrystallized Calcite (CaCO3) Rock

Porfido (Porphyritic Rock)

Porphyry (often Rhyolitic or Andesitic)

Moss Agate

Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite

Citrine Quartz

Silicon Dioxide (SiO2) with iron impurities

Dendritic Opal

Hydrated Silica (SiO2·nH2O) with Manganese or Iron Oxide inclusions

Labradorite

Labradorite ((Ca, Na)(Al, Si)4O8)

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.

Bloodstone (also known as Heliotrope)

Silicon Dioxide (SiO2) - variety of Chalcedony

Desert Rose

Selenite Rose (Gypsum: CaSO4·2H2O)

Pink Granite

Phaneritic Felsic Igneous Plutonic Rock

Pink Granite

Phaneritic Felsic Intrusive Igneous Rock

Aura Quartz

Titanium/Titanium-Gold treated Silicon Dioxide (SiO2)

Aqua Aura Quartz

Titanium/Gold-coated Silicon Dioxide (SiO2)

Citrine Quartz

Citrine (Silicon Dioxide, SiO2)

Gold Nugget

Native Gold (Au)

Fire Agate

Agate (Variety of Chalcedony), SiO2 (Silicon Dioxide)

Labradorite

Labradorite ((Ca,Na)(Al,Si)4O8)

Graphic Granite

Pegmatitic Feldspar and Quartz (Graphic Granite)

Heat-Treated Citrine (Amethyst Geode Fragment)

Silicon Dioxide (SiO2) with iron impurities

Slag (Industrial Glass)

Anthropogenic Amorphous Vitreous Silicate

Garden Quartz (Phantom Quartz)

Silicon Dioxide (SiO2) with various inclusions (often Chlorite, Hematite, or Iron)

Chrysocolla

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

Fire Agate

SiO2 (Silicon Dioxide with Iron Oxide inclusions)

Gold-bearing Quartz with Iron Oxides

Quartz (SiO2) with Limonite/Goethite (FeO(OH)) and Pyrite (FeS2)

Iolite (Cordierite)

Cordierite (Magnesium Aluminum Silicate), Mg2Al4Si5O18

Marble (Fire and Ice or Pink Veined)

Metamorphosed Limestone (principally CaCO3)

Dalmatian Stone

Peralkaline Quartz-Feldspar Rock with Arfvedsonite

Sunstone with Black Tourmaline (Arfvedsonite)

Feldspar (Na,Ca)(Al,Si)4O8 with Schorl Na(Fe3+)3Al6(Si6O18)(BO3)3(OH)3(OH)

Basalt with Quartz/Calcite Veins

Basalt (Aphanitic Mafic Volcanic Rock) with Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3) inclusions

Rutilated Quartz

Quartz with Rutile Inclusions (SiO2 with TiO2 inclusions)

Labradorite

Labradorite ((Ca, Na)(Al, Si)4O8)

Porphyritic Rhyolite (Red)

Rhyolite (Porphyry)

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic silicate with secondary mineral inclusions)

Moss Agate

Silicon Dioxide with inclusions (SiO2)

Healer's Gold (Pyrite/Magnetite in Serpentine)

Magnetite (Fe3O4) and Pyrite (FeS2) in Lizardite/Antigorite [Mg3Si2O5(OH)4]

Labradorite

(Ca, Na)(Al, Si)4O8 (Plagioclase Feldspar)

Labradorite

Labradorite ((Ca, Na)(Al, Si)4O8)