Ore forming processes Flashcards
(27 cards)
What is the distribution of gold deposits?
Unequal
What is the origin of gold and what are deposits like?
Igenous and concentrated in weathering and sedimentary basins
How does gold being a soft mineral affect is deposits?
Malleable, easily isolated and fragmented from host rock (reason for being found in placer deposits)
What is the potential lifespan of gold?
> 30yrs
What are the trends in gold prices?
Gold price historically stable with slow rates of increase, rare drops
Less affected by market volatility than stock and
shares
Price increase when geopolitical uncertainty
How long has hard rock mining been taking place in the US?
100yrs
What does the US EPA suggest is the effect on water surrodung old gold mines?
estimates contributed to contamination of 40% of
country’s rivers and 50% of all lakes
What is the problem with the US trying to remidiate abandoned gold mines?
Original companies no longer exist no down to local and national government so little to no funding
What is artisinal mining?
mineral extraction by individuals, cooperatives, or small companies with minimal capital investment and with much use of manual labour
What is industrial scale gold mining like?
Large scale hard rock extraction
Large scale placer deposit surface extraction from fluvio-glacial sand and gravel deposits
Large scale dredging from nearshore ocean settings following old river systems from last glacial maximum
sourced from gold bearing source rocks
When might large gold companies use artisinal?
for site survey, the artisinal say where the gold they find is so big comapnies know where to do deep mining
What is the sustainability of gold like?
Finite resource, but as commodity becomes rarer marginal reserves worked and exploration increases to new site
What are most artisinal gold mine deposits like?
placer
What bonus to large companies get by using artisinal companies to survey an area?
Use artisinal as propectors to give a likely value for the site which they can show to shareholders and increase stock price and make profit without rick of mining losses
What are blood diamonds with countries they are commonly from?
Diamonds mined in a war zone and sold to finance insurgency and invading armies
Liberia, Angola, Ivory Coast, Sierra Leone
What problem is associated with trying to prevent blood diamonds?
by the time they are cleaned and have made it to diamond market it is hard to tell where they are from
WHat legislation is in place to reduce blood diamonds?
Kimberley Process Certification-Scheme (2000)
World Diamond Council (2001)
What is the purpose of the kimberley process sertification scheme?
Resolution to strengthen the diamond
industry’s ability to block sales of conflict
diamonds
What is the purpose of the world diamond council?
Certification of diamonds source to confirm not from conflict zones
Why has cobalt mining increased?
To match the need of consumer goods and electric vehicles boom for batteries
Where is the majority of cobalt mining and majority of refining?
Mining - 75% DRC
Refining - 70% China
How is cobalt acquired?
Cobalt ores not usually mined outright - often recovered as a by-product of mining iron, nickel, copper, silver, manganese, zinc and arsenic
What is the processing of cobalt like?
Complex to extract and concentrate from the ores
How is the landscape affected by cobalt mining?
Loss of vegetation
Poor air quality (toxic)
Waste pollution leaching into rivers water sources
Decreased crop yields
