Mineraloid

Pink Granite

Phaneritic Felsic Igneous Rock

Tiger's Eye (with Hematite/Jasper)

SiO2 (Silicon Dioxide) with Fe2O3 (Hematite)

Chert or flint nodule

Microcrystalline quartz (SiO₂), commonly chalcedony with possible opaline silica

Greenstone / altered mafic rock

Likely chlorite–actinolite schist or metabasalt; exact identification requires testing

Gabbro

Gabbro (composed mainly of calcium-rich plagioclase feldspar and pyroxene)

Dragon Blood Jasper

Microcrystalline Quartz (Chalcedony) with Epidote and Piemontite

Snowflake Obsidian

Volcanic Glass with Cristobalite inclusions

Polished pale stone, likely limestone or quartzite pebble

Most consistent with micritic limestone (calcite, CaCO₃), though the image cannot confirm mineralogy

Sandstone

Quartz Arenite (a common type of sandstone, given the appearance), Arkose, Greywacke (depending on mineralogy)

Iron-rich meteorite candidate

Undetermined stony-iron or iron meteorite; mineralogy likely Fe–Ni metal with silicates

Jasper and Greenstone Pebble

Siliceous rock / Metamorphic pebble

Banded River Rock / Gneiss (highly weathered)

Gneiss

Howlite

Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)

Charoite

Charoite (K(Ca,Na)2Si4O10(OH,F)·nH2O)

Hypersthene

Enstatite (Hypersthene variety), (Mg,Fe)SiO3

Serpentinite (probable)

Serpentinite, dominated by serpentine-group minerals (Mg₃Si₂O₅(OH)₄), with dark magnetite or chromite and pale carbonate/talc possible

Dragon Blood Jasper

Quartz (SiO2) with Epidote and Piedmontite inclusions

Tumbled sodalite (probable)

Sodalite, Na₈(Al₆Si₆O₂₄)Cl₂; possibly blue-dyed jasper or lapis lazuli

Prasiolite and Quartz Crystal Cluster

Quartz (SiO2); Prasiolite is a variety of Quartz

Tumbled gray stone, likely serpentinite or weathered basalt

Tentatively serpentinite (predominantly serpentine-group minerals); identification is uncertain from the photograph

Chert (Green River Chert)

Microcrystalline Quartz (SiO2)

Gneiss

Gneiss (a type of metamorphic rock)

Polished orbicular granite (likely K2-type granite)

Granite, chiefly quartz, alkali feldspar, plagioclase, and dark amphibole/biotite; possible epidote-rich orbicules

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Greisen

Greisen

Orbicular basalt (amygdaloidal basalt)

Basalt, commonly with iron-oxide–stained amygdules; matrix chiefly plagioclase, pyroxene, and often olivine

Hypersthene

(Mg,Fe)SiO3 - Enstatite-Ferrosilite series

Pegmatite (likely Granitic Pegmatite)

Pegmatite (a coarse-grained igneous rock, often with granitic composition)

Chert (specifically Silex or Flint)

Microcrystalline Quartz (SiO2)

Likely polished leopard-skin jasper or brecciated jasper

Jasper, an opaque microcrystalline variety of quartz (SiO₂), with iron-oxide and other mineral inclusions; exact variety cannot be confirmed from the image alone

Onyx (Calcite Onyx / Mexican Onyx)

Calcium Carbonate (CaCO3)

Dendritic Agate (or Dendritic Opal)

SiO2 (for Agate), SiO2·nH2O (for Opal)

Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Ocean Jasper (Orbicular Jasper)

Silica (SiO2) with varied mineral inclusions

Green Obsidian Sphere (man-made glass)

Vitreous Silica with Chromium/Iron additives

Sugilite

Sugilite (KNa2(Fe,Mn,Al)2Li3Si12O30)

Banded Gneiss

Gneiss (pronounced 'nice')

Pearl (likely Freshwater or Akoya Cultured)

Aragonite / Conchiolin composite (CaCO3)

Granite (likely a river or beach pebble)

Granite (a felsic intrusive igneous rock primarily composed of quartz, feldspar, and mica)

Cubic Zirconia

Zirconium dioxide (ZrO2)

Hypersthene (or Enstatite/Ferrosilite)

Orthopyroxene series (Mg,Fe)SiO3 - specifically, historically hypersthene (intermediate member) now referred to as Enstatite (Mg-rich) or Ferrosilite (Fe-rich)

Pebble (likely a type of sandstone or quartzite pebble)

Clastic Sediment (specifically, a rudite-sized clast). If the pebble is composed of a specific rock type, its scientific name would be that rock type (e.g., 'Quartzite pebble', 'Granite pebble', 'Chert pebble'). Given its appearance, it is likely a metamorphic quartzite pebble or a hard sandstone pebble.