Sedimentary (Secondary Mineral) Within Igneous

Labradorite (tumbled)

Labradorite (a plagioclase feldspar mineral between anorthite and albite; chemical formula: (Ca,Na)(Si,Al)4O8)

Basalt

Basalt (primarily composed of Plagioclase Feldspar and Pyroxene)

Porphyritic Basalt

Amygdaloidal Porphyritic Basalt

Limonite (Iron-rich Siltstone / Sandstone base)

Hydrous ferric oxide mixture (FeO(OH)·nH2O)

Porphyritic Basalt (with Quartz or Calcite inclusion)

Porphyritic Basalt (Matrix: SiO2/MgO/FeO, Phenocryst: likely Quartz or Calcite)

Basalt

Mafic Extrusive Igneous Rock

Brecciated Chert

Brecciated Chert (Microcrystalline Quartz, SiO2)

Turquoise

Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]

Jasper Agate

Chalcedony (Silicon Dioxide - SiO2)

Yellow Quartz (Chalcedony)

Silicon Dioxide (SiO2)

Beach Agate (Chalcedony)

Silicon Dioxide (SiO2)

Amygdaloidal Basalt with Quartz/Zeolite Infill

Amygdaloidal Basalt (extrusive volcanic rock with SiO2 or CaAl2Si3O10·3H2O infill)

Wonderstone (Banded Rhyolite)

Rhyolite (Silicon Dioxide with Iron Oxide impurities)

Ruby (Corundum)

Corundum (Aluminum Oxide with Chromium), Al2O3:Cr

Native Sulfur

Sulfur (S)

Satin Spar (Selenite)

Gypsum (CaSO4·2H2O)

Fluorite

Calcium Fluoride (CaF2)

Veined Quartz

SiO2 (Silicon Dioxide)

Sandstone with Liesegang Rings

Arenite with Iron Oxide Liesegang Banding

Basalt (Amygdaloidal)

Amygdaloidal Basalt

Amygdaloidal Basalt

Amygdaloidal Basalt (extrusive volcanic rock)

Diamond

Diamond (Carbon, C)

Limonite (Iron Ore/Hydrated Iron Oxide)

Limonite (mixture of FeO(OH)·nH₂O minerals, mainly Goethite, FeO(OH) and Lepidocrocite, FeO(OH))

Snakeskin Agate

Agate (Cryptocrystalline Quartz, SiO2)

Basalt

Extrusive mafic igneous rock; primarily (Ca,Na)(Mg,Fe,Al,Si)2O6 with (Ca,Na)(Al,Si)4O8

Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Basalt

Basalt (Mafic Extrusive Igneous Rock)

Rhodochrosite

Manganese carbonate (MnCO3)

Granodiorite Pebble

Granodiorite (containing Quartz, Plagioclase Feldspar, and Biotite/Amphibole)

Milky Quartz

Crystalline Silicon Dioxide (SiO2)

Fluorite in Matrix

Fluorite (CaF2) within a host rock matrix

Dalmatian Stone

Dalmatian Jasper (a misnomer) / Perthitic Igneous Rock

Diamond

Carbon (C)

Sandstone (Ferruginous)

Arenite (composed primarily of SiO2 with Fe2O3 staining)

Magnetite

Iron(II,III) oxide (Fe3O4)

Gneiss

Gneiss (High-grade metamorphic rock)

Calcite with iron staining

Calcium Carbonate (CaCO3)

Red Jasper (Opaque Chalcedony)

Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions

Bronzite

Enstatite (var. Bronzite), (Mg,Fe)SiO3

Agate

Silicon Dioxide / Cryptocrystalline Quartz (SiO2)

Moss Agate

SiO2 (Silicon Dioxide) with dendritic inclusions

Amygdaloidal Rhyolite

Amygdaloidal Rhyolite (Felsic volcanic rock)