Mineral, Often A Rock Given Its Aggregate Nature

Amazonite

KAlSi3O8 (Potassium Feldspar, variety of Microcline)

Basalt

Basalt (Mafic volcanic rock)

Shale

Shale (Lutite)

Milky Quartz

Silicon Dioxide (SiO2)

Muscovite Mica

Muscovite (KAl2(AlSi3O10)(OH)2)

Green Jasper

Microcrystalline Quartz (Chalcedony), SiO2

Black Tourmaline (Schorl)

Schorl (NaFe3Al6(BO3)3Si6O18(OH)4)

Shale

Argillaceous Sedimentary Rock

Rhodonite

Rhodonite (Mn2+SiO3)

Druzy Quartz

Crystalline Silicon Dioxide (SiO2)

Unknown Dark Stone

Unknown

Jasper

Silicon Dioxide (SiO2) with impurities

Quartzite Cobble

Quartzite (SiO2)

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.

Jasper

Microcrystalline quartz (SiO2)

Basalt (Porphyritic)

Porphyritic Basalt

Jasper

Silicon Dioxide (Microcrystalline Quartz, SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Chert (Tan/Brown variety)

Chert (Silicon Dioxide, SiO2)

Agate

SiO2

Gold in Quartz Matrix

Native Gold (Au) with Quartz (SiO2) and Slate/Shale

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Blue Topaz

Aluminum Silicate Fluoride Hydroxide - Al2SiO4(F,OH)2

Red Breccia Jasper

Silicon Dioxide (SiO2) with hematite and various mineral inclusions

Basalt River Stone

Extrusive Igneous Rock

Pyrite (on Shale/Matrix)

Iron Disulfide (FeS2)

Granite

Phaneritic Felsic Igneous Rock

Quartz (Milky or Cloudy Quartz)

Silicon Dioxide (SiO2)

Sandstone (River Cobble)

Sandstone (primarily composed of silica, SiO2)

Blue Lace Agate (Tumbled)

Silicon Dioxide (SiO2)

Blue Howlite (Dyed)

Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)

Quartz Pebble

Silicon Dioxide (SiO2)

Lava Rock (Basalt)

Basalt (extrusive igneous rock)

Chert (Flint)

Chert (predominantly SiO₂ - silicon dioxide)

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Red Jasper

Silicon dioxide (SiO2) with hematite impurities

Jasper (brecciated or orbicular variety)

Silicon dioxide (SiO2) with iron oxide inclusions

Malachite-Bearing Copper Ore

Cu2CO3(OH)2 (Malachite) in host rock

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).

Quartz Pebble

Silicon Dioxide (SiO2)

Shale (or Mudstone)

Clay mineral aggregate / Fine-grained siliciclastic sedimentary rock

Quartzite pebble

Quartzite (SiO2)