Mineral Based Composite

Polished greenstone pebble

Likely serpentinite (serpentine-group minerals); identification from appearance alone is uncertain

Turquoise cabochon

Turquoise, CuAl₆(PO₄)₄(OH)₈·4H₂O; likely stabilized or matrix-bearing

Gold

Native gold (Au)

Muscovite Mica

Muscovite KAl2(AlSi3O10)(OH)2

Likely tumbled jasper or agate

Microcrystalline quartz (SiO₂), possibly jasper or chalcedony

Tree Agate

Silicon Dioxide (SiO2) with Dendritic Inclusions

Dendritic Agate

Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions

Green Moss Agate

Agate (Silicon Dioxide, SiO2) with inclusions

Quartzite (Aventurine type)

Metamorphosed Quartz Sandstone (SiO2 with inclusions)

Sandstone

Arenite (mostly Quartz-based)

Quartz vein material

Quartz (SiO₂), likely milky quartz with iron-oxide staining

Calcite crystal cluster

Calcite (calcium carbonate, CaCO₃)

Polished blue spotted stone, likely K2 stone

K2 stone: granite containing blue azurite spots; quartz–feldspar–biotite matrix

Red Moss Agate (Jasper)

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Water-worn Pebble

Lithified detrital rock fragment

Brecciated jasper (likely)

Silica-rich jasper/chert breccia, composed mainly of microcrystalline quartz (SiO₂)

Purple Turquoise (Composite Mojave Turquoise)

CuAl6(PO4)4(OH)8·4H2O (Hydrated copper aluminum phosphate composite)

Moon (lunar surface depiction)

Lunar rock; chiefly anorthosite, basalt, and breccia (plagioclase-rich CaAl2Si2O8)

Gold

Gold (Au)

Gold

Native Gold (Au)

Gold

Gold (Au)

Tumbled turquoise cabochon

Turquoise, CuAl₆(PO₄)₄(OH)₈·4H₂O; possibly stabilized or dyed material

Pebble

Lithified clastic rock fragment / Quartz-rich pebble

Botryoidal calcite specimen

Calcite, CaCO₃, with possible dolomite or other carbonate matrix

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.

Polished pietersite-like brecciated jasper

Silicified chalcedony/jasper aggregate, primarily SiO₂; exact material uncertain from image

Gold Nugget Jewelry

Native Gold (Au)

Conglomerate

Conglomerate (clastic sedimentary rock)

Bumblebee Jasper

Anhydrous Calcium Carbonate with Sulfur and Arsenic (Orpiment/Realgar)

Mixed Mineral Collection (Quartz, Amethyst, Rose Quartz, Pyrite, etc.)

Mixed Silicates and Sulfides (SiO2, FeS2)

Blue Sapphire

Corundum (Al2O3)

Turquoise cabochon (likely stabilized or imitation)

Turquoise, hydrated copper aluminum phosphate: CuAl₆(PO₄)₄(OH)₈·4H₂O

Blue-green chrysocolla rough specimen

Chrysocolla, hydrated copper aluminosilicate; commonly associated with malachite, quartz, and limonite

Tumbled yellow jasper or chert

Microcrystalline quartz (SiO₂), likely iron-oxide-stained chalcedony/chert

Cubic Zirconia

Zirconium Dioxide (ZrO2)

Tumbled orbicular jasper

Orbicular jasper; microcrystalline quartz (SiO₂) with iron oxides and feldspathic/chalcedony inclusions

Green Moss Agate

Silicon Dioxide (SiO2) with Mineral Inclusions

Moss Agate

Silicon Dioxide (SiO2) with inclusions of manganese or iron oxides

Weathered granite pebble

Granite, chiefly quartz (SiO₂), feldspar, and minor mica

Blue-green cabochon pendant, likely turquoise or composite turquoise

Turquoise: hydrated copper aluminum phosphate, CuAl₆(PO₄)₄(OH)₈·4H₂O; exact identification is uncertain from the blurred image

Unakite

Altered Granite (Epidotized Granite)

Moss Agate

Silicon Dioxide (SiO2) with Chlorite/Hornblende inclusions