1. Minerals & Mining
Lesson 3

2. General Mining Law (1872) 1872 – do you think it was good or bad??
Encouraged settlement of western states
Anyone can stake a mining claim on federal lands, buy for $ $5 per acre, extract the resources, & keep all profits.
No provisions for environmental protection
Image from Wikimedia Commons

3. …General Mining Law (1872)
More than 50 of the 100,000 to 500,000 abandoned mines in the US are Superfund sites! Cleanup of all Superfund mining sites will cost an estimated $12.5-$17.5 billion.

4. Minerals
Elements or compounds of elements that occur naturally in Earth’s crust.
Ex: steel (mixture), aluminum, copper, concrete (mixture), sulfur, salt, quartz, gold, … you get it.
Changed the course of history…
Britain = explored for tin.
Bronze Age = ruled by the alloy of copper & tin.
New World = explored for gold & silver.
California = gold rush (1840s)
Rain forests destruction = gold

5. …Minerals Mineral Groups: Can be:
NATURALLY OCCURRING
INORGANIC
SPECIFIC CHEM. COMP.
SOLID
DEF. CRYSTAL STRUCTURE
Mineral Groups:
Sulfides (S + another element)
Oxides (O + metals)
Halides (F, Cl, Br, I)
Silicates (Si + O)
Carbonates (C + O)
Native Elements (any pure element)
Can be:
Metallic
Nonmetallic
Rocks = combo of minerals + other stuff
Ore = rock that contains a large enough concentration of a mineral that makes it profitable to mine for.
High-grade ore: large amounts of minerals
Low-grade ore: low amounts of minerals.

6. Distribution & Formation
Widely distributed worldwide (see next slide)
Some countries have a lot, some have a little.
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Magmatic Concentration
Magma cools & separates into layers
Heavy (Fe, Mg) on bottom, Light (SiO2) on top
Hydrothermal Processes
Hot groundwater dissolves minerals & react with S, making sulfides
Sulfides aren’t soluble, so they settle out.
Sedimentation
Water transports weathered particles and deposits them as sediment
Evaporation
Salts & minerals are left behind when water evaporates.

7. How is mining done?
STEP 1: DISCOVER THEM! STEP 2: EXTRACT THEM! STEP 3: PROCESS & REFINE THEM! STEP 4: MAKE THEM INTO A PRODUCT!

8. Step 1: DISCOVERY
Aerial or Satellite photography Measure Earth’s magnetic field & gravity Geological knowledge of how minerals form Drill for samples & analyze composition Sea floor?? Detailed 3D maps!

9. Step 2: EXTRACTION 2 ways: Surface & Subsurface Mining!
Surface Mining (less $$, less danger)
Overburden must be removed
4 Kinds:
Open-pit mining = dig a big hole to make a quarry.
Strip Mining = dig parallel trenches and create a spoil bank (dump new trench’s overburden in old trench)
Mountaintop Removal = BAD!!!
Dredging = chain buckets & draglines scrape underwater minerals
Subsurface Mining (more $$, more danger)

10. Step 3: PROCESSING Smelting
Melting ore at high temperatures to help separate impurities from the molten metal.
Uses a Blast Furnace
Ore, coke, and limestone react with heat to create:
Purified molten iron (denser)
Iron Ore + Coke = molten iron + carbon dioxide
Impurities (“Slag”) (less dense)
Limestone + Impurities = slag
Exhaust gases are dangerous!

11. … that means… Create a Product!!
Step 4: CREATE PRODUCT
… that means… Create a Product!!

12. Increasing our Mineral Supplies
Locating & Mining New Deposits
Minerals in Antarctica
Minerals from the Ocean
Advanced Mining Techniques

13. Increasing our Supplies… Locating and Mining New Deposits
Sometimes we know there are resources out there… but they’re inaccessible.
Malaria in Indonesia, Ice in Antarctica, High sedimentation in Amazon Basin
Create new technologies
Dig 10km below surface, go through ice sheets, etc.
Possible to find new resources?? USGS: sure!

14. Increasing our Supplies… Minerals in Antarctica
To date, no substantial mineral deposits have been found in Antarctica.
But we might find some!
FYI – nobody owns Antarctica… so the rules can get sticky when people want to exploit resources.
ANTARCTIC TREATY – 1961
Limits activity in Antarctica to peaceful uses such as scientific studies.
Environmental Protection Protocol to the Antarctic Treaty (Madrid Protocol) – 1990
Moratorium on mineral exploration and development for >50yrs
People are already ruining Antarctica’s fragile ecosystem… science, tourism, noise, pollution…

15. Increasing our Supplies… Advanced Mining Technologies
Use more low-grade mineral deposits.
$$$$$$$$$$$$$$$
Causes greater land disruption
Produces far more pollution than high-grade ores
In arid regions, lots of water needs to be pumped in to help with the mining process.
Biomining
Microorganisms can extract minerals from low-grade ores
Copper mining uses it.
They help!!
90% recovery of gold with them
75% recovery without them.

16. Expanding our Supplies by Substitution and Conservation
Finding Mineral Substitutes
Use inexpensive, abundant materials instead!
Old=Tin. New=plastic, glass, aluminum.
Old=Copper wires. New=fiber optics (glass).
Mineral Conservation – important!! (they’re nonrenewable!)
Reuse & Recycle
Changing our Mineral Requirements
Become a low-waste society!
Sustainable manufacturing (minimize waste in industry)
Dematerialization
Decrease weight of products.

17. RELEVANT LEGISLATION General Mining Law (1872)
Allowed people to “stake claims” & make profit
Surface Mining Control and Reclamation Act (1977)
Required reclamation of previously mined areas
Only from coal mining!!
Antarctic Treaty (1961)
Limits activity in Antarctica to peaceful uses such as scientific studies
Convention on the Regulation of Antarctic Mineral Resource Activities (1980s)
Never ratified – would have permitted exploitation of Ant. minerals
Environmental Protection Protocol to the Antarctic Treaty (Madrid Protocol) (1990)
Moratorium on mineral exploration & development for >50 years
Designated Antarctica & its marine ecosystem as a “natural reserve dedicated to peace and society”