Lecture 5 - Ressources from Our Changing Planet

people overpopulation

too many people living in a given geographic area

consumption overpopulation

each individual consumes too large a share of reassources

overpopulation

leads to increased use of resources and destruction of environment

human energy consumption

we use aluminum the most (86%), 76% of harvested timber, 61% meat and 42% fresh water, we also generate 75% of pollution and waste

non-renewable ressources

we have a limited supply and it doesnt regenerate or it does but very slowly, this includes fossil fuels like oil, gas and coal which takes millions of years to accumulate, nuclear fuel which raises concerns about safety and waste, minerals like iron, aluminum, industrial minerals like gravel and sand, critical minerals like lithium, nickel, colbalt, etc for green and digital economy, there are environmental impacts related to mining and our consumption of these ressources is changing the earth

minerals and mining

this is important to Canada’s economy as it generates 156 million dollars in revenue which is 5% of Canada’s GDP, Toronto is the global center of mining and mineral exploration finance, gold makes up most of the profits (26%)

critical minerals

important for green/digital economy and security, they are in increased global demand and needed to support important manufacturing sectors like communication tech, aerospace and national security, also low-carbon and digital technology, the ring of fire is in northwestern ontario where lots of chromium deposits are located, economically viable

primary mineral deposits

those found in host rock, examples include hydrothermal ore deposit and gold (industrial so found in an open pit or underground)

secondary mineral deposits

those that are found after moving, examples would be deposit and gold nugget, requires artesinal mining so panning or dredging

what are the 5 steps of the mineral ressources cycle

exploration, discovery, development, production and reclammation

exploration

treasure hunt, looking for new deposits we can extract

discovery

actually doing the field work to find the gold

development

found deposit and characterized it, gonna try and extract it now so this is where the engineers come in

production

separating the ore from the host rock, lots of mechanical processes here

reclamation

during operations, this creates value of the land, return land to end use

production types

includes underground, open pit and strip mining

drift

horizontal tunnel that accesses the mineral

bingham canyon

located in utah, its an open pit copper mine, its the largest man made excavation and deepest open pit mine, its 1.2 km deep and 4 km wide

mine tailings

examples include gold and oil sands, for gold the ore typically contains 1g/ton of precious mineral and the ore gets crushed so the gold can be removed from rock by acid leaching, for oil sands bitumen is removed from sand using hot water

efemcukuru gold mine

a sustainable mining operation in western turkiye, partly owned by eldorado gold, vein ore deposits requires underground mining to follow the deposit to depth, in lifetime of operation it is estimated that 8.5 million tons of ore will be mined, estimated mine life of 7 years which is a relatively short time

what is gold?

it is a native chemical element (Au), it is dense, soft, malleable and ductile, very non-reactive chemically, it is used in jewelry, electrical connectors, IR shielding and teeth, it is mainly used as a common financial standard, alloyed with other metals to strengthen it, the karat measures its purity where 24 is 100% pure and 18 is 75% pure, etc

ore processing

crushing and multistage floatation to separate ore from host rock, gravity processing to separate gold

sustainability

backfill excavation, filtered waste water with cement for backfill, slope stabilization and rehabilitation with olive groves

diamonds

a natural mineral, solid form of carbon with atoms in cubic diamond crystal structure, hardest known natural material

how are diamonds created?

they are created beneath the lithosphere at high pressure (4-6 GPa, 150-200 km beneath the surface), they are then brought to the surface in kimberlite pipes, volcanic ultramafic magma from mantle possible containing diamond xenoliths

who owns most of the world’s gold?

the US government has the largest reserve, most of it is in fort knox and the rest in a bank in new york city, India and China come second in owning the most gold

what is the value of your diamond based on?

the cut, colour, clarity and carat

cut of diamond

92% of diamonds globally are cut in Surat, India, it optimizes the brightness of your diamond, when the light transmits back out of the diamond giving its sparkle that’s called round brilliant cut, a properly cut one takes into account internal reflection of light in the diamond, an ideal cut internally reflects the light back out to make a more brilliant diamond, the light enters through the facets of the diamond (planar surfaces)

colour of diamond

this is influenced by chemical or structural impurities in diamond, huge variation in colour, although some are especially rare

clarity of diamond

flaws in diamonds can result from inclusion fractures during cutting, most natural diamonds have inclusions so the flawless diamonds have the most value, the inclusions can give us interesting scientific info on age/conditions in the earth’s mantle

carat of diamond

this refers to the size not to be confused with karat which measures gold purity, 1 carat is equivalent to 0.2 gram diamond, its just the weight of it

hope diamond

this is a famous diamond in the smithsonian museum in washington which is believed to be cursed

cullinan diamond

this was discovered in south africa, its on king charles’ crown, its the largest gem quality diamond ever found