Minerals and Mineral Identification

Lecture & Deliverables Schedule (S2025)

• The schedule outlines lectures, tutorials, and deliverables for the GeoE/EnvE 153 course.
• Key dates include:
  • May 05: No class due to design days.
  • May 09: Make-up lecture in RCH 112.
  • May 12: Continuation of L2 and L3: Weathering and Erosion.
  • May 19: No lecture due to Victoria Day.
  • May 23: Case Study Deliverable 1 due at 11:30pm ET.
  • May 26: Term Test #1 (Up to Earth Systems) in EIT 1015 & MC 2017.
  • June 02: L8: Sedimentary Rocks.
  • June 06: Make-up lecture in RCH 112; Case Study Deliverable 2 due at 11:30pm ET.
  • June 09: Continuation of L10 and L11: Mechanics of Rock Materials II.
  • June 13: Soils Lab "Appendices" Due Friday Jun 13 @ 11:30pm ET.
  • June 16: L11: cont. as needed.
  • June 23: Term Test #2 Midterm Week - No Lectures/No Tutorials (Up to MechofRckMats) in EIT 1015 & MC 2017.
  • June 27: Make-up lecture in RCH 112.
  • June 30: No lecture due to Canada Day.
  • July 04: Case Study Deliverable 3 Due Friday.
  • July 07: L14: Surface Water II
  • July 11: Make-up lecture in RCH 112.
  • July 14: L16: cont. as needed.
  • July 18: Case Study Deliverable 4 Due Friday, Jul 18 @ 11:30pm ET.

The Nature of Minerals

• Minerals are defined by five key characteristics:
  1. Naturally occurring
  2. Inorganic
  3. Solid
  4. Ordered internal molecular structure
  5. Characteristic & Consistent chemical composition and identifiable physical properties

Minerals

• Of the 4000+ identified minerals, only a few hundred are common and important in geology and civil engineering.
• Over 90% of Earth’s crust is composed of minerals from 5 groups: feldspars, pyroxenes, amphiboles, micas, quartz.

Mineral Resources and Geologic Processes

• Mineral deposits form as part of the rock cycle.

Why Minerals, Rocks & Soils Matter

• Every engineering structure interacts with rocks or soils.
• Rocks and soils are composed of a heterogeneous assortment of minerals.
• Minerals are partially responsible for the physical and chemical properties of rocks & soils.

Minerals: The Building Blocks of Rocks

• Minerals are like ingredients in bread; they must be properly combined.
• The bread analogy: Minerals are like eggs, flour, sugar, yeast, and salt. When baked under heat, pressure, and time, they form a "bready rock."

Minerals in Our Products

• Minerals are ubiquitous in everyday products, including:
  • Silica and lithium in glasses
  • Aluminum in cans
  • Gypsum in wallboard
  • Copper, nickel, and zinc in coins
  • Tungsten in lightbulbs
  • Titanium, chromium, iron, cadmium, and others in wall paint
  • Iron, chromium, manganese, nickel, and others in steel
  • Silver and gold in jewelry
  • Tantalum in cell phones
  • Titanium, zinc, iron, copper, and others in cosmetics
  • Copper and zinc in brass belt buckles
  • Lead in solder
  • Iron in pen ink
  • Zinc and manganese in batteries for radios
  • Nickel and cadmium in batteries for laptops
  • Lead, platinum, hafnium, gallium, indium, tantalum, and others in laptops
  • Salt in food

Evolution of Humans & Minerals

• Bronze Age: 1000 BC
• Stone Age: A long time ago
• Concrete & Roman Coliseum: 0 BC
• RCA building, Rockefeller Center, New York: 1932

Where the Minerals Are

• The slide shows a map of the world highlighting the countries that have the most reserves for a variety of minerals.
• Highlights include:
  • United States: Copper (7%), Hafnium (9%), Indium (10%), Lead (14%), Phosphorus (7%), Silver (14%), Zinc (20%), Uranium (10%)
  • Canada: Indium (33%), Lead (6%), Nickel (10%), Silver (6%), Uranium (10%), Zinc (7%)
  • Cuba: Nickel (16%)
  • Morocco & Western Sahara: Phosphorus (42%)
  • Mexico: Silver (7%)
  • Jamaica: Aluminium (8%)
  • Niger: Uranium (6%)
  • Guinea: Aluminium (27%)
  • Peru: Copper (6%), Gold (5%), Silver (7%), Tin (9%)
  • Chile: Copper (38%)
  • Poland: Copper (5%), Silver (25%)
  • Russia: Indium (5%), Nickel (6%), Platinum/Rhodium (8%), Antimony (recoverable) (10%)
  • China: Aluminium (7%), Antimony (62%)
  • Kazakhstan: Chromium (60%)
  • India: Chromium (7%)
  • South Africa: Antimony (5%), Chromium (35%), Platinum/Rhodium (88%)
  • Brazil: Aluminium (8%), Hafnium (26%), Tantalum (48%)
  • Namibia: Uranium (8%)
  • Bolivia: Antimony (8%)
  • Malaysia: Tin (11%)
  • Australia: Aluminium (24%), Copper (5%), Gold (7%), Hafnium (53%), Lead (19%), Nickel (19%), Silver (7%), Tantalum (52%), Uranium (23%), Zinc (17%)
  • Indonesia: Nickel (9%), Tin (8%)
  • New Caledonia: Nickel (8%)

Atoms and Elements (Review)

• An element is a substance that cannot be broken down into others by ordinary chemical reactions.
• An atom is the smallest unit of a substance that retains the properties of that element.
  • Composed of 3 types of subatomic particles:
    • Protons (positively charged)
    • Neutrons (zero net charge)
    • Electrons (negatively charged)
• A molecule is the smallest unit of a compound that retains the properties of that substance.

Composition of Earth’s Crust

• Common Elements:
  • Nearly 97% of the atoms in Earth’s crust are represented by the 8 most common elements: O, Si, Al, Fe, Ca, Na, K, Mg
• Common Mineral Types:
  • Most minerals are silicates (contain Si and O bonded together)
• Minerals have crystalline structures
  • Regular 3-D arrangement of atoms

Isotopes

• Atoms of an element with different numbers of neutrons are called isotopes.
• Isotopes may be either stable or unstable.
  • Stable isotopes retain all of their protons and neutrons over time.
  • Unstable or radioactive isotopes spontaneously lose subatomic particles from their nuclei.
• Stable isotopes can be used to track climate change over time.

Radiocarbon Dating Method

• Carbon is an important element found in all forms of life.
• Three isotopes: Carbon 12 and 13 are stable, whereas carbon 14 (C^{14}) is radioactive. Dating is based on the ratio of C^{14} to C^{12}.
• All carbons are absorbed in a nearly constant ratio by all living organisms. When an organism dies, C^{14} is not replenished, and the ratio of C^{14} to C^{12} decreases.

Mineral Groups

• The mineral groups include:
  1. Silicates
  2. Oxides & Hydroxides
  3. Sulphides
  4. Sulfates
  5. Native Elements
  6. Halides
  7. Carbonates
  8. Phosphates

Silicates

• Ferromagnesian (dark) silicates contain ions of iron or magnesium (or both) in their structure.
• Non-ferromagnesian (light) silicates contain ions of aluminum, potassium, calcium, sodium (or combinations) in their structure instead of iron and magnesium.
• Melting temperature increases from non-ferromagnesian to ferromagnesian silicates.

Common Silicate Minerals

• Non-Ferromagnesian Silicate Group:
  • Feldspar:
    • potassium feldspar = microcline and orthoclase; pinkish hue
    • plagioclase feldspar = white to cream color
    • cleave along two internal planes of weakness
    • common in all three major rock groups
  • Quartz
  • Muscovite (mica, but colorless)

Silicates (Clay Minerals)

• Clay is a term to describe complex minerals with a sheet structure, similar to micas.
• Clays are usually derived from the chemical alteration (weathering) of other silicates, mainly feldspars.
• Clay minerals comprise a large percentage of surface material (soil).
• Clay minerals include groups like Kaolinite, Smectite, Illite, and Chlorite.

Non-Silicate Minerals

• Carbonates: Contain CO3 in their structures (e.g., calcite - CaCO3)
• Sulfates: Contain SO4 in their structures (e.g., gypsum - CaSO4 \cdot 2H_2O)
• Sulfides: Contain S (but no O) in their structures (e.g., pyrite - FeS_2)
• Oxides: Contain O, but not bonded to Si, C, or S (e.g., hematite - Fe2O3)
• Native elements: Composed entirely of one element (e.g., diamond - C; gold - Au)

The Structure of Minerals (Halite)

• Halite (NaCl) demonstrates the orderly arrangement of sodium and chloride ions.

What is Salt?

• NaCl – halite (rock salt)
• An “evaporite” rock formed from the evaporation of water in restricted flow basins.
• Beds can be up to 2000 m thick in some basins.
• Deep salt beds give rise to salt domes (diapirs).
• Highly useful to society for many reasons.

Salt Applications

• Industrial mineral (feedstock, deicing…)
• Nuclear waste repositories (DE, DK, US)
  • Salt is essentially impermeable
  • Salt flows slowly (viscous) and seals itself
  • Salt is accessible (<1000 m), widespread
• Natural gas storage (and other fluids)
  • Hundreds of caverns around the world
• Slurried waste disposal in salt caverns
  • Used in AB, SK, ON, Texas…

Salt Cavern Underground Natural Gas Storage Reservoir Configuration

• Diagram illustrates the use of salt caverns for underground natural gas storage.

Salt in Ontario

• Goderich Mine is the biggest UG Salt mine in North America
• Other locations include Windsor, London, and Sarnia.

Goderich Mine, Ontario

• The largest underground salt mine in North America.

Underground in Goderich

• Speed Limits are displayed underground.

Polymorphs of Carbon

• Diamond and graphite are polymorphs of carbon.
• Polymorph - some elements can join in more than one geometric arrangement
  • Chemical composition stays the same
  • Physical properties differ
  • Example: diamond and graphite

Mineral Resources

• Table 2.4 lists common nonsilicate mineral groups with their members, formulas, and economic uses.
• Examples include:
  • Oxides (Hematite, Magnetite, Corundum, Ice)
  • Sulfides (Galena, Sphalerite, Pyrite, Chalcopyrite, Bornite, Cinnabar)
  • Sulfates (Gypsum, Anhydrite, Barite)
  • Native elements (Gold, Copper, Diamond, Sulfur, Graphite, Silver, Platinum)
  • Halides (Halite, Fluorite, Sylvite)
  • Carbonates (Calcite, Dolomite, Malachite, Azurite)
  • Hydroxides (Limonite, Bauxite)
  • Phosphates (Apatite, Turquoise)

Metallic Mineral Resources

• Lists metals and their principal ores, along with geological occurrences.
• Examples include:
  • Aluminum (Bauxite)
  • Chromium (Chromite)
  • Copper (Chalcopyrite, Bornite, Chalcocite)
  • Gold (Native gold)
  • Iron (Hematite, Magnetite, Limonite)
  • Lead (Galena)
  • Magnesium (Magnesite, Dolomite)
  • Manganese (Pyrolusite)
  • Mercury (Cinnabar)
  • Molybdenum (Molybdenite)
  • Nickel (Pentlandite)
  • Platinum (Native platinum)
  • Silver (Argentite, Native silver)
  • Tin (Cassiterite)
  • Titanium (Ilmenite, Rutile)
  • Tungsten (Wolframite, Scheelite)
  • Uranium (Uraninite)
  • Zinc (Sphalerite)

More Minerals

• Ore minerals:
  • Minerals of commercial value ($)
  • Most are non-silicates (primary source of metals)
  • Examples: magnetite and hematite (iron), chalcopyrite (copper), galena (lead), sphalerite (zinc)
  • Must be able to be extracted profitably to be considered current resources
• Gemstones:
  • Prized for their beauty and (often) hardness
  • May be commercially useful
  • Black diamond, corundum, and quartz are used as abrasives

Major Mineral Resources of Canada

• Map shows the location of mineral resources in Canada by province or territory, including:
  • Yukon Territory: Ag, C, Pb, Au, Cd, Zn, Ba, Cu
  • Northwest Territories: Ag, NG, W, Au, Pb, Zn, Cu, Pet
  • British Columbia: Ag, Cd, Pb, Asb, Cu, Pet, Au, Fe, RE, Ba, Gyp, S
  • Alberta: Ba, Bent, Pet, S, C, Salt, Mg, Si
  • Saskatchewan: Ag, NG, Au, Gyp, Te, Bent, S, Cd
  • Manitoba: Ag, Cd, Gyp, Asb, Cu, Pb, F, Si, Fe, Zn
  • Ontario: Au, M, Ti, Oll Ss, Cd, Pb, Cd, Se, Co, Pet
  • Quebec: Ag, F, Talc, Asb, Fe, Te, Bent, Ni, Zn
  • New Brunswick: Ag, Cu, Sb, Au, Gyp, W
  • Nova Scotia: Ba, Salt
  • Prince Edward Island: Si

Canada: World Mining Leader

• The TSX is the world's largest exchange for metal mining stocks.

Mineral Resources in Ontario

• Lists mineral resources in Ontario and their abbreviations.
• One of the most valuable mineral resources in Ontario, based on the value of annual production over time, is Nickel.
  • Ag – silver
  • Asb – asbestos
  • Au – gold
  • Ba – barium
  • Ca – calcium
  • Cd – cadmium
  • Co – cobalt
  • Cu – copper
  • Dol – dolomite
  • Fe – iron
  • Gyp – gypsum
  • Mg – magnesium
  • NG – natural gas
  • Ni – nickel
  • Nes – nepheline syenite
  • Pb – lead
  • Pet – petroleum
  • PGM – platinum group metals
  • RE – rare earth elements
  • Salt - salt
  • Se – selenium
  • Si – silicon
  • Sn – tin
  • Talc – talc
  • Te – tellurium
  • U – uranium
  • Zn - zinc

Nickel mine (Sudbury, Ontario)

• Image of Nickel mine in Sudbury, Ontario.

Nickel tailings pond (Sudbury, Ontario)

• Image of Nickel tailings pond in Sudbury, Ontario.

Asbestos (Thetford Mine, Quebec)

• Image of Asbestos in Thetford Mine, Quebec.

Asbestos: Risks?

• Mineral which easily separates into long, thin, strong fibres.
• Heat resistant and inert material used commonly in insulation, fireproof fabrics, cement, floor tiles, automobile brakes, and siding for older homes.
• Canada (Quebec) is the world’s top exporter and second largest producer of chrysotile (white asbestos).
• Cancer and lung problems originate with brown and blue asbestos (amphibole), leading to a number of countries banning the substance outright.

Concrete (Anthropogenic) Aluminum Silicates

• Hydraulic cement (Portland) manufactured from large supplies of high-quality limestone, gypsum, and clay/shale, sourced by local concrete producers.
• Aluminum Silicates:
  • Belite (2CaO \cdot SiO_2)
  • Alite (3CaO \cdot SiO_2)
  • Tricalcium aluminate (3CaO \cdot Al2O3)
  • Brownmillerite (4CaO \cdot Al2O3 \cdot Fe2O3)
  • Gypsum (CaSO4 \cdot 2H2O)
• Others:
  • Lime (CaO)
• Aggregates:
  • sand/gravel
  • Silica (SiO_2)
• Water (H_2O)
  • (for hydration of minerals)

Concrete Calcium Carbonate

• Non-hydraulic cement contains:
  • Calcium Carbonate (CaCO_3
  • Aggregates:
    • sand/gravel
    • Silica (SiO_2)
  • Water (H_2O)
    • (for hydration of minerals)
• Chemical reactions:
  • CaCO3 \rightarrow CaO + CO2
  • CaO + H2O \rightarrow Ca(OH)2
  • Ca(OH)2 + CO2 \rightarrow CaCO3 + H2O

Diamonds

• First Canada production in 1998 at Ekati mine, Lac de Gras, NWT; Diavik, 2003; Snap Lake (2007+)
• Formation:
  • Carbon crystallized at depths > 160 km
  • Carried quickly into crust in rising magma called kimberlite, a serpentinized, mica peridotite, mainly olivine and pyroxene minerals
  • Easily weathered and under lakes in NWT; found by tracing indicator minerals in glacier material, geophysics
• Need 5000 + carats for a mine
• Minimum ore grade: 0.5 carats/ton
• 1 carat = 200 mg

Diamonds Exploration Methods

• Combination of various approaches:
  1. Tracing indicator minerals (distinct, abundant in Kimberlite, unique to Kimberlite) in glacial deposits to the “up-ice” source (need ice movement direction indicators)
  2. Magnetic anomalies:
     • Circular anomaly resulting from remnant magnetic field of Kimberlite pipe (airborne detection, under glacial deposits). The signature is not unique but distinctive
  3. Depressed topographic position as Kimberlites and easily eroded (e.g., Lac de Gras lakes, NWT)

Snap Lake Diamond Mine

• Image of Snap Lake Diamond Mine.

Ekati Diamond Mine NWT

• Satellite Image of Ekati Diamond Mine NWT.

Diavik Diamond Mine

• NWT produced 13% of the world’s diamonds in 2008.
• NWT GDP tripled from $1.5 billion in 1991 to $4.5 billion in 2007.
• Unemployment dropped from 13.7 to 5.4%.

Diavik Diamond Mine - Challenges

• Significant challenges:
  • On an Island / Remote
  • Northern Climate, Permafrost, No Roads
  • Kimberlite Pipe is under Lac de Gras
  • Pit slope stability
  • Tailings Where???
  • Eventual transition to Underground mining
  • Environmental Challenges
    • Wildlife
    • Tundra
    • Lac des Gras – very pure water

Years remaining if production continues to grow at current rates

• Years remaining if production remains static

Let's Move on to Mineral Identification! (LAB INFO)

• Transition to Mineral Identification lab information.

Mineral Properties – The Definitions

• Color: Visible hue of a mineral.
• Streak: Color left behind when mineral is scraped on unglazed porcelain.
• Luster: Manner in which light reflects off the surface of a mineral.
• Hardness: Scratch-resistance.
• Crystal form: External geometric form.

Mineral Properties (cont.)

• Cleavage: Breakage along flat planes.
• Fracture: Irregular breakage.
• Specific gravity: Density relative to that of water.
• Magnetism: Attracted to magnet.
• Chemical reaction: Calcite fizzes in dilute HCl.

Physical Properties of Minerals: Colour

• Some minerals can have several different colours, so colour is a poor definitive identification property.
• Examples: Amethyst (purple quartz), Citrine (yellow quartz), Smoky quartz (gray to black)

Physical Properties of Minerals: Colour

• Colour may vary as a result of minute amounts of impurities.
• General guidelines for colour:
  • Ferromagnesian silicates (Fe, Mg-bearing) are generally black, brown or dark green.
  • Non-ferromagnesian silicates are often light in appearance.

Physical Properties of Minerals: Streak

• Test colour of the powered mineral by the (ceramic) streak plate.
• The colour of the powdered mineral [its streak colour] is less prone to variation than colour of the mineral form itself.

Physical Properties of Minerals: Lustre

• Lustre may be metallic or non-metallic:
  • Metallic: reflects light only from the surface of the mineral; may have “brilliant” or “dull” appearance
  • Non-metallic: reflects light from within as well as from the surface of the mineral
• Examples:
  • Metallic: Strong reflections produced by opaque substances
  • Vitreous: Bright, as in glass
  • Resinous: Characteristic of resins, such as amber
  • Greasy: The appearance of being coated with an oily substance
  • Silky: The sheen of fibrous materials, such as silk
  • Pearly: The whitish iridescence of such materials as pearl
  • Adamantine: Brilliant, like a diamond

Physical Properties of Minerals: Hardness

• Mohs Scale of Hardness:
  • 10: Diamond
  • 9: Corundum
  • 8: Topaz
  • 7: Quartz
  • 6: Potassium Feldspar
  • 5: Apatite
  • 4: Fluorite
  • 3: Calcite
  • 2: Gypsum
  • 1: Talc
• Hardness of Common objects:
  • 5.5 Glass, Pocketknife
  • 3 Copper Penny
  • 2.5 Fingernail

Physical Properties of Minerals: Crystal Form

• When a mineral is permitted to grow freely, it will develop well-formed crystal faces.
• Most of the time, intergrowth of crystals occurs and often none exhibit its crystal form.

Cleavage and Fracture

• Cleavage = property of individual mineral crystals.
• May split or break along lines defined by the strength of the bonds within the mineral crystal.
• Cleavage can be defined in terms of:
  • quality (perfect, good, poor)
  • direction
  • angles of intersection of cleavage planes
• Fracture is mineral breakage along uneven surfaces.

Cleavage and Fracture cont.

• Examples of minerals exhibiting cleavage planes: Fluorite (4 cleavage planes), halite (3 planes at right angles) and calcite (3 planes at 75 degrees).
• Conchoidal Fractures in Volcanic Glass / Obsidian
• Irregular Fractures in Quartz

Common Mineral Example Illustration of Sketch Cleavage Directions

• Diagram shows common minerals and their corresponding number of cleavage directions. (Muscovite, Orthoclase, Amphibole, Calcite, Halite)

Physical Properties of Minerals: Specific Gravity

• Specific \, Gravity = \frac{Weight}{Weight \, of \, equivalent \, volume \, of \, water}
• Typical values:
  • Ferromagnesian silicates = 2.7 to 4.3
  • Non-ferromagnesian silicates = 2.6 to 2.9
  • Galena = 7.58
  • Hematite = 5.26
  • Graphite = 2.09 to 2.33
  • Diamond = 3.5

The Acid Test: Carbonate Minerals

• Calcite reacts vigorously with dilute hydrochloric acid.
• Dolomite does not react with acid unless it is powdered.
• Powdering dolomite creates effervescence.

The Final Word .. ..

• A humorous slide depicting the varying perceptions of what a geologist does.