adapted to HTML from lecture notes of Prof. Stephen A. Nelson Tulane
Reserves vs. Resources
Reserves - Are dependent on price.
Resources - Total amount of material present.
(Notice that the production of gold roughly followed the price of the
gold. In 1980 the price of gold drastically went up and very shortly after
that we see a sharp increase in gold production. This sharp increase
reflects the addition of other gold sources that were previously thought
too costly to use.)
Typically a gold mine may contain 10 grams (one-third of an ounce) of gold
per ton of ore mined.
involved in deciding whether to mine a potential ore body
Price of commodity
Size of ore body
Cost of capital investment
Underground vs. Surface Mining ( underground mining is much more
expensive generally will only do this if there is a seam or if the ore
can be sold at a high price)
Extent of mineral processing necessary (eg- 8 g of gold is recovered
from 1 ton of rock)
Cost of mining
Cost of transportation
Cost of reclamation (returning land to previous pre-mining
Is there a market?
Mineral Reserves and Resources
World Reserve 1,000 tons
World Lifetime Years
U.S. Reserves 1,000 tons
The Rise of Recycling
Notice how the consumption of metals has changed from a strictly primary
source to a 50% primary source and 50% recycled source since about 1980.
Another overhead has to do with what % of scrap metal for a variety of
different metals were used instead of mining new reserves. The below is a
list of the findings.
% of scrap metal used
Environmental Problems associated with various aspects of Mining
Exploration - Need to put in roads, cut lines through woods, etc.
Underground - Not as bad, except that sometimes hazardous materials
Surface - Pit or strip mine. Can cover very large tracrts of land.
Waste materials need to be disposed of, and are often toxic.
Smokestack - Ejects toxic material into the atmosphere.
Sulfides are common - Arsenic, lead, mercury, sulfuric acid.