Sedimentary (Secondary Mineral Formation)

Clear Quartz

Silicon dioxide (SiO2)

Chalcedony (Agate) Pebble

Silicon Dioxide (SiO2)

Calcite

Calcite (Mineral, Calcium Carbonate - CaCO3)

Chalcedony (Agate/Carnelian pebbles)

Cryptocrystalline Quartz (SiO2)

Yellow Jasper / Chalcedony

Silicon Dioxide (SiO2) with iron inclusions

Quartz (Yellow/Citrine variety or Iron-stained Quartz)

Silicon Dioxide (SiO2)

Waterworn pebble, possibly iron-rich basalt or river stone

Unidentified lithic clast; composition cannot be determined reliably from the image

Clear Quartz

Silicon Dioxide (SiO2)

Blue Calcite

Calcium Carbonate (CaCO3)

Green Calcite

Calcium Carbonate (CaCO3)

Agate

Cryptocrystalline Silicon Dioxide (SiO2)

Yellow Quartz Pebble

Silicon Dioxide (SiO2)

Red Jasper (Polished)

Silicon Dioxide (SiO2) with Hematite inclusions

Red Jasper

Silicon Dioxide (SiO2) with Hematite impurities

Quartz Crystal Cluster

Silicon Dioxide (SiO2)

Milky Quartz Nodule / Geode precursor

Silicon Dioxide (SiO2)

Orange Calcite point

Calcite (Calcium Carbonate, CaCO3)

Blue Calcite

Calcium Carbonate (CaCO3)

Turquoise (Rough)

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

Orange Calcite

Calcium Carbonate (CaCO3)

Milky Quartz

Silicon Dioxide (SiO2)

Carnelian Agate

Carnelian (Chalcedony / Silicon Dioxide SiO2)

Limonite with Iron Inclusions

Limonite (Hydrated Iron Oxide, FeO(OH)·nH2O)

Quartz Pebble (likely Chalcedony or Quartzite)

Silicon Dioxide (SiO2)

Psilomelane (Manganese Ore)

Psilomelane (Ba,H2O)2Mn5O10

Small brown pebble or possible shell fragment

Unidentified natural clast; the image is too small and blurred for reliable identification

Banded Iron Formation

Banded Iron Formation (BIF)

Milky Quartz with Iron Staining

Silicon Dioxide (SiO2)

Small brown mineral fragment

Unidentified; the image lacks enough detail for a reliable species-level identification

Quartz (Iron-Stained)

Silicon Dioxide (SiO2)

Limonite (Iron Ore)

Hydrated ferric oxide (FeO(OH)·nH2O)

Turquoise

CuAl6(PO4)4(OH)8·4H2O

Small tan rock fragment

Unidentifiable lithic fragment; mineral composition undetermined

Unidentifiable embedded dark fragment

Indeterminate; possibly a dark silicate mineral or lithic inclusion

Vesicular basalt (possibly weathered scoria)

Basaltic volcanic rock; chiefly plagioclase, clinopyroxene, and Fe–Mg oxides, with vesicles from trapped gas

Banded Iron Formation (Fragment)

Banded Iron Formation (BIF)

Limonite or Ironstone

Hydrated iron oxide-hydroxide, approximately FeO(OH)·n(H2O)

Botryoidal Hematite (Iron Ore)

Iron(III) oxide (Fe2O3)

Banded Agate

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Weathered iron-rich concretion or sedimentary rock

Likely ferruginous sandstone or ironstone concretion; exact identification is not possible from the image alone

Quartz (Citrine / Yellow Quartz)

Silicon Dioxide (SiO2)

Native Copper (Penny specimen)

Native Copper (Cu)