Sedimentary (Chemically Precipitated Mineral)

Fluorite

Fluoride (Calcium Fluoride - CaF2)

Red Jasper

Jasper (Silicon Dioxide, SiO2 with iron oxide impurities)

Chert (with Limestone/Dolomite host)

Microcrystalline Quartz (SiO2)

Ironstone (likely siderite or goethite-rich siltstone)

Ferruginous Siltstone

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz Pebble (Tumbled / River Pebble)

Silicon Dioxide (SiO2)

Septarian Nodule or Mud Crack Fossil

Septarian Nodule (Concretion)

Limonite Pseudomorph after Pyrite

Limonite (FeO(OH)·nH2O) replacing Pyrite (FeS2)

Chert (White Chert)

Silicon Dioxide (SiO2)

Graphite

Graphite (Native Carbon, C)

Optical Calcite (Iceland Spar)

Calcite (Calcium Carbonate, CaCO3)

Chert with Chalcedony/Quartz Vug

Cryptocrystalline Silica (SiO2)

Chert

Chert (Microcrystalline Quartz, SiO2)

Halite

Halite (Sodium Chloride, NaCl)

Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Banded Sandstone

Arenite with iron oxide banding

Jasper

Microcrystalline Quartz (SiO2)

Quartz

Silicon Dioxide (SiO2)

Chalcopyrite (Peacock Ore)

Chalcopyrite (CuFeS2)

Chert (Flint / Chalcedony pebble)

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Jasper (Chert)

SiO2 (Microcrystalline Quartz with Iron Oxide impurities)

Red Jasper (or Ironstone Pebble)

SiO2 (Quartz/Microcrystalline Chalcedony with Hematite inclusions)

Gold Nugget

Native Gold (Au)

Turquoise

Turquoise (CuAl6(PO4)4(OH)8·4H2O)

Turquoise

CuAl6(PO4)4(OH)8·4H2O

Yellow Chert (Chert / Cryptocrystalline Quartz)

Silicon Dioxide (SiO2)

Granodiorite

Granodiorite (Phaneritic intrusive igneous rock containing Plagioclase, Quartz, and Biotite/Amphibole)

Azurite with Malachite

Azurite: Cu3(CO3)2(OH)2 / Malachite: Cu2CO3(OH)2

Chert Pebble

Chert (Microcrystalline Quartz, SiO2)

Quartz Crystal Cluster

Silicon Dioxide (SiO2)

Caliche (also known as hardpan, calcrete, kankar)

Primarily composed of calcium carbonate (CaCO₃), often mixed with other minerals like quartz, clay minerals, and iron oxides.

Flint

SiO2 (Microcrystalline Quartz / Chert)

Concrete fragment with Aggregate

Anthropogenic Concrete with Calcarious and Siliceous Aggregate

Chert

Chert (Microcrystalline Quartz, SiO2)

Chert (Jasper variation)

Chert (Cryptocrystalline microcrystalline Silicon Dioxide, SiO2)

Yellow Chert (Jasper)

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon dioxide (SiO2)

Chert (Flint)

Chert (Microcrystalline Quartz, SiO2)

Weathered sandstone or siltstone

Clastic sedimentary rock, chiefly quartz and feldspar grains cemented by clay, silica, or iron oxides

Ironstone with Pyrite

Ferruginous Sandstone (Fe2O3) with minor Sulfide minerals (FeS2)

Limestone

Calcium Carbonate (CaCO3)