Minerals

Metallic vs Non metallic

Metallic: gold, lead, copper, silver

Nonmetallic: gypsum, sand, limestone, clay, coal

Ore minerals: a mineral with a high concentration of metals that are easily extracted

• have a high concentration of strategic elements than basic rock forming materials

• Formation: ore deposit, economically significant deposit of metallic ore

• Resources: the total amount of a geologic material in all its deposits discovered and undiscovered

• Reserves: the discovered deposits of a geologic material that are economically and legally feasible to recover

  • must be: Discovered, Recoverable, Legal, Profitable

  • Unrecoverable: reactive minerals (Na, or Al), metals that have similar chemical composition, fine particle size, Gangue (unwanted materials)

Ore Formation Deposits

Magnetic Deposits: heavy metals crystallize and sink to the bottom of a magma chamber

1. Common deposits: Cr, Pt, Ni, Fe, and Cu

2. Platinum Group Metals (PGM): Pt, and palladium

   • minor: Au, Ag, Ni, Cu

3. Pegmatite: very coarse crystalline, intrusive, igneous rock

   • fills thick veins (looks like large cliffs)

   • contains granite plutons= Boron, F, Li, U, and gems

4. Kimberlites: mantle sourced ultramafic intrusions becoming diamonds

   • very dark, small chunks

Metamorphic Processes: Hydrothermal, Metasomatism, Volcanogenic Massive Sulfides

1. Hydrothermal deposits: hot fluids filled with dissolved ions filled veins, cool, and minerals precipitate

   • water rises from magma chamber and combines with meteoric water, is pushed out of narrow chambers to the top of a caldera as boiling hot spring

2. Metasomatism: ore mineralization during contact metamorphism with introduction of ions from an external source

   • water carrying Iron ions in magma surrounded by marble and limestone is pushed out of the chamber. At point of contact metamorphism is changes the marble to magnetite, and water continues to escape

3. Volcanogenic Massive Sulfides: from underwater vents/volcanoes. Hot water is instantly cooled and forms sulphide minerals (black smoke)

   • sea water enters the crust through narrow chambers and is heated up by a magmatic heat source. Metals that are leached from volcanic rock donate ions to the water as it circulates back up to the surface of the crust. Once It passes through an ore body (volcano/thermal vent) and instantly cools once in contact with sea water again, forming a sulphide material.

Weathering Processes

1. Residual mineral deposits: leaching of metallic ions through soils

2. Secondary-Enrichment deposits: erosion and accumulation of rock with metallic minerals

   • rock becoming exposed by weathering

   • minerals weathered by ground water

3. Placer Deposits: erosion and accumulation of rock with metallic minerals

   • Weathered materials from a zone of weathering is transported down through erosion processes, underground metallic material travels with the weathered rock. And is deposited into stream which build a placer

   • gold panning

4. Banded Iron Formation (from ancient oceans)

   1. Oxidation at redoxcline with biologically produced oxygen

      • formed through Fe from underwater vents rising and reacting with oxygen produced by photosynthesis. And Fe oxide falls to the water bank causing iron deposits with banded formations

      • Shallow carbonates = no bands

      • Granular formation = red and black bands

      • Banded Fe = red, black, and green

   2. Direct Oxygenation with an-oxygenic photosynthesis

      • formed through Fe from underwater vents rising and reacting with micro-photosynthsizers who oxidize the Fe directly (not from photosynthesis), leaving iron chemocline. With Fe oxide falling to the water bank causing iron deposits with banded formations

      • Shallow carbonates = no bands

      • Granular formation = red and black bands

      • Banded Fe = red, black, and green

   3. Abiogenic Iron Deposition

      • only in precambrian rocks

      • formed through Fe from underwater vents rising and reacting with Si and carbonates and O2, leaving iron chemocline, and iron banded formation on water banks

      • Shallow carbonates = no bands

      • Granular formation = green and black

      • Banded Fe = green and black

Non-metallic Resources

1. Crushed Stone: gravel, snad, limestone

2. Dimension Stone: gypsum, salt, clay, coal

   • evaporating sea water to get salts and electrolyte compounds