Mineral, Often A Rock Given Its Aggregate Nature

Shale

Lutaceous sedimentary rock

Conglomerate

Conglomerate Rock (Paraconglomerate)

Scoria (Volcanic Rock)

Scoria (often basaltic scoria)

Igneous

Chrysocolla in Matrix

Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O (Silicate/Secondary Copper Mineral)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Sandstone (Ferruginous)

Arenite (Siliclastic Sedimentary Rock)

Shale

Fissile mudrock (composed primarily of clay minerals and quartz)

Mineral, specifically an iron ore

Iron Ore / Ironstone Concretion

Mixture of iron oxide/hydroxide minerals, likely some combination of Hematite (Fe2O3), Goethite (α-FeOOH), and Limonite (a general term for hydrated iron oxides of variable composition) or potentially Bauxite (a mixture of aluminum hydroxides, often with iron oxides, (Al(OH)3) and FeO(OH)). The visual characteristics strongly suggest iron-rich material.

Grey Agate (Tumbled)

Silicon Dioxide (SiO2)

Muscovite Mica

Muscovite (KAl2(AlSi3O10)(OH)2)

Shale

Laminated Mudstone

Shale

Lutaceous Sedimentary Rock

Anthropogenic (Man-made material mimicking sedimentary rock)

Concrete Fragment

Hardened Portland Cement Composite

Chalcedony (Agate)

Silicon Dioxide (SiO2)

Howlite and Purple Amethyst Druzy

Calcium Borosilicate Hydroxide (Howlite) and Silicon Dioxide (Quartz/Amethyst)

Sandstone (Weathered Pebble)

Arenite (primarily SiO2)

Yellow Agate

Silicon Dioxide (SiO2)

Lava Rock (Basalt)

Basalt (extrusive igneous rock)

igneous

Limonite (after Pyrite Pseudomorph)

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

Banded Agate (specifically Carnelian Agate color)

Silicon Dioxide (SiO2) - variety of Chalcedony

Chert (Tan/Brown variety)

Chert (Silicon Dioxide, SiO2)

Pebble (likely Quartzite or Chert)

Clastic Sediment, potentially composed of SiO₂ (Quartz)

Mineral, Sediment

Chalcedony (Banded/Mottled Variety)

Chalcedony (a cryptocrystalline variety of Quartz, SiO2)

Picture Jasper

Silicon Dioxide (SiO2) with iron oxide and clay inclusions

Amazonite

KAlSi3O8 (Potassium Feldspar, variety of Microcline)

Chert (Flint)

Chert (predominantly SiO₂ - silicon dioxide)

Rough Topaz

Aluminum silicate fluoride hydroxide [Al2SiO4(F, OH)2]

Mica Group Minerals

There isn't a single scientific name as 'Mica' refers to a group of phyllosilicate minerals. Common scientific names include Muscovite (KAl₂ (AlSi₃O₁₀)(OH)₂), Biotite (K(Mg,Fe)₃AlSi₃O₁₀(OH)₂), Phlogopite (KMg₃AlSi₃O₁₀(OH)₂), and Lepidolite (K(Li,Al)₃(Al,Si,Rb)₄O₁₀(F,OH)₂).