What is the true value of gold?

What is the true value of gold?

There’s something about gold. It possesses us, sometimes entire nations to accumulate more and more of it. Humans have had a strong affinity for gold since the times of the ancient Egyptians and the Aztecs. Gold has been used as currency for thousands of years. Wars have been fought for it, entire civilizations slaughtered for their gold.  Pindar, the ancient Greek poet, described gold as “a child of Zeus, neither moth or rust devoureth it, but the mind of man is devoured by this supreme possession.”

goldCoins

It’s hard to describe the feeling of finding your first gold nugget in an old stream bed.  It sits there in your pan shimmering, the way that only gold can.  You immediately recognize it’s power, it is intoxicating.  This is what drives prospectors past and present to take great risks in the search for gold.  There’s more than just the value of gold that attracts us to it.  The word “placer” itself comes from the Spanish word meaning “pleasure”. For some it is an addiction, for others it symbolizes wealth. You’ll be hard pressed to find a member of the human species who wouldn’t be interested in some gold.

Gold has several properties that make it desirable.  Most importantly it does not rust or tarnish.  Gold artwork discovered in the tombs of Egypt looks just as lustrous today as it did 5000 years ago.  Why is that?  Gold belongs to a group of metals called the “Noble Metals”.  They’re called noble because like nobility in old time monarchies they don’t associate with others.  It’s fancy way of saying that the metals don’t readily react.  Conversely iron will readily react with oxygen to form iron oxide (aka rust).  Gold and other noble metals, such as platinum, possess a very strong atomic structure that requires a lot of energy to disrupt.

KingTut

The ability to maintain over time is common of all valuable substances.  A diamond for example produces a characteristic glow when cut and faceted properly but what good would it be if it disintegrated a month later?  Diamonds are extremely hard and have a rock solid crystal structure.  Other valuable gemstones all share similar properties, emeralds, rubies, sapphires and garnets all sit at the high end of the hardness scale.  While gold isn’t hard in a geological sense it maintains it’s shape and luster indefinitely.

Gold is also very malleable.  Meaning that it can be hammered or pressed into various shapes without cracking or losing its consistency.  You could stretch an ounce of gold into a wire 80km long or produce a sheet of gold leaf 80 meters by 80 meters wide.  Gold is also an excellent conductor.  Not quite as good as copper but a better conductor than nickel, brass, iron, tin, and aluminium.  Gold conductive wire is used in many critical electronics applications such as computer motherboards, smart phones and satellites.

CarajasMine
Carajás iron mine, Brazil

What really makes gold valuable though is it’s scarcity at the earth’s surface.  Approximately 165,000 metric tons of gold have been produced in the entirety of human history.  While that may sound like a lot the amount of gold produced by mining is extremely small in comparison to other metals.  For example the Carajás Mine in Brazil produces an average of 300 million metric tons of iron per year and has a deposit estimated at 7.2 billion metric tons.  And that’s just one mine.  All the gold ever produced would fit inside one Olympic sized swimming pool.

It is often stated that you can’t eat gold.  While that’s not entirely true, (see gold covered pizza) an all gold diet wouldn’t provide much nutrition, and you’d probably have some digestive issues.  The yellow metal doesn’t appeal to our basic needs for survival but neither does money or a smartphone.  That doesn’t make any of these things less valuable.

gold-400oz-bar

 

We typically think of value in dollar terms.  When evaluating an investment such as stocks or real estate it’s hard to think of anything else.  Dollars are not constant though, they are subject to manipulation and inflation.  For at least 6000 years gold has been used as currency and unlike modern currency is not subject to inflation.  Modern currencies are what is called “Fiat Currency”.  There is no standard on what a modern currency note can be exchanged for.  Their value relies solely on people’s faith in it.  Or more correctly their faith in the government.  Inflation rates can severely affect the spending power of a dollar.  There are countless examples, the most striking is the inflation of the German Reichsmark which rose from 4.2 marks to USD in 1914 to a peak of around 4.2 trillion marks to the US dollar by November 1923.  At that time a wheelbarrow full of German marks wouldn’t even buy a newspaper.

Historically world currencies were backed by the gold standard which meant that by law any amount of paper money could be exchanged for a specified amount of gold.  In the 1920s each US dollar was backed by 1.5 grams of gold.  The dropping of the gold standard in Germany during WWI allowed for the hyperinflation that followed.  The United States dropped the standard during the great depression to avoid the federal gold supply from being completely depleted.  Canada followed suit in 1933.  There’s much debate on the merits of dropping the gold standard.  What resulted though is the ability for the government to completely control the currency without requiring tangible assets (ie. gold) to back it up.

Gold bars
Gold bars

So if the dollar is backed by nothing and can be manipulated at will how do you gauge the value of gold.  Or anything for that matter.  True value depends on what people are willing to trade for your goods.  Money makes it easy to barter and trade goods since it’s ubiquitous and there is an agreed upon value at any given time.  For example if you want to sell your car on craigslist you’ll have an idea of how many dollars you want for it.  Lets say you have a used Honda Civic.  You could sell that easily for $4000 CAD.  That same Honda Civic could be traded for a 1 carat diamond engagement ring.  50 years from now a used car might sell for $25,000 dollars due to inflation but the exchange rate of car to diamond ring would remain the same.

The old adage that an ounce of gold will buy you a nice suit still rings true today.  In the gold rush era (1848-1900) an ounce of gold would trade for about $20 USD, and would also buy a nice suit.  A typical suit today would cost you about $450 USD.  So it would seem that today’s gold would buy you 3.5 nice suits.  You have to consider that in the 1800s nice clothing was not mass produced.  To compare accurately you’d have to look at a tailored suit.  A mid range tailored suit made in the United States costs between $1650 and $1800 today.   At present gold is trading at about $1250 USD so the suit adage falls just above the quoted dollar value of gold.

Indian River Yukon

What really gives gold it’s value is the cost of exploration and production.  Being very rare it takes a lot of effort to find gold.  Once it’s found it is expensive to produce as well.   For example Barrick’s Cortez mine in Nevada has an average grade of 2.11 grams per ton.  That means that for every ton of ore processed they average 2.11 grams of gold.  Barrick’s published production cost at the Cortez mine is about $900/oz.  It really is remarkable that they can move and process the 15 tons of rock required to obtain an ounce of gold for $900.

The cost of producing an ounce of gold varies for each mine.  In a placer operation it is a constant cat and mouse game to keep costs low enough to make production economical.  When gold commodity prices fall below production costs mines shut down and less and less gold is produced.  The production cost, driven by scarcity is the single most important factor that drives the price of gold.

RC Drill in Action

Gold exploration is also very expensive.  In the times of the North American gold rush placer and hard rock gold was discovered all over the Western part of the continent.  From the 1840s to 1900 new gold districts were popping up every year as discoveries were made.  Trending almost in sequence Northward from California to the Yukon as explorers made their way through the wilderness.  In more modern times most of the easily reachable areas have have been at least partially explored.  Exploration today mostly takes place in more and more remote areas, such as the Canadian Arctic or other places with a small human footprint.

To properly explore a claim in these areas requires a camp. helicopters and all kinds of equipment.  A typical small exploration program in the Northwest Territories can cost well over $1,000,000 per season with slim chances of success.  While advancements in exploration technology such as geophysics and aerial imagery can provide information that wasn’t available to previous explorers there is no silver bullet.

The costs of thousands of exploration ventures that didn’t amount to a mine are factored into the price of gold as well.  For the estimated 100,000 explorers that took part in the Yukon gold rush only a select few managed to recoup their costs.  Some made made great discoveries but many more spent their life savings on an adventure but returned with no gold.

Big Al Jig

Gold’s value is based on it’s unique properties, people’s desire for the very special metal and the work required to find and produce it.  The value has nothing to do with the the dollar value attached to it.  For every ounce of gold produced tons of rock had to be excavated, the deposit had to be discovered and mapped, and the ore milled and smelted to extract the gold.  As you gaze upon your gold ring and admire it’s beauty think about the story that it could tell you.

Share Button

Mining the Ocean Floor with Robots

Mining the Ocean Floor with Robots

Mining under Earth’s oceans is just starting to happen.  We have gotten pretty good at mining deposits that are accessible by land but 71% of the Earth’s surface is covered by water.  To date no large scale mining operation has succeed under the ocean which means that it’s all virgin ground.

Amazingly the human race has spent more time and money exploring outer space than we have under our own oceans.  Over 500 people have been to space while only three have ventured to the deepest part of the ocean, the Mariana Trench.  We have better maps of the surface of Mars than the bottom of the ocean, although the ocean maps are pretty cool.

ocean_floor_map

The same geological processes that happen on land also take place under the ocean.  There are volcanoes, mountain chains, faults and earthquakes.  All the same types of mineral deposits occur under the ocean such as epithermal gold, porphyry, and placer.  There are also diamond pipes, massive sulphides and everything else that we mine at the surface.

Deposits

The ocean also has types of deposits that we can’t find on land.  One special mineral deposit is called Polymetallic Nodules.  These are concretions of metallic minerals that occur under the ocean.  The nodules grow sort of like stalactites do in a cave, over time layers of metallic minerals precipitate out of seawater and add to the nodule.  The growth of nodules is one of the slowest known geological processes taking place at a rate of one centimetre over several million years.

noduleBig2nodules_floor

Polymetallic nodules are roughly the size and shape of a potato and contain primarily manganese as well as nickel, copper, cobalt and iron.  They can be found on the sea floor or buried in the sediment.  Nodules can technically occur anywhere in the ocean but seem to be in greatest abundance on the abyssal planes around 5000m deep.  Nodule mining would be similar to placer gold mining except under water.

Anouther resource that is unique to the ocean floor is Ferromanganese Crusts.  These are similar to nodules but occur as a coating on other rocks.  These crusts can be found all over the ocean with thicknesses ranging from 1mm to 26cm.  Ferromanganese crusts typically occur in the vicinity of underwater volcanoes called seamounts or near hydrothermal vents.  Crusts with mineral grades that are of economic interest are commonly found at depths between 800m and 2500m.

Crust
Ferromanganese Crust

Ferromanganese crusts are composed primarily of iron and manganese, hence the name.  Typical concentrations are about 18% iron and 21% manganese.  Cobalt, Nickel and Copper occur in significant quantities as well.  Rare earth metals such as Tellurium and Yttrium can be found in metallic crusts at much higher concentrations than can be found on the surface.  Tellurium is used in solar panels and is quite valuable.

Sea-floor massive sulphides (SMS) are a younger version of volcanic massive sulphides (VMS).  The two deposits are similar except that VMS are typically ancient and SMS are currently forming.  SMS deposits occur where superheated hydrothermal fluids are expelled into the ocean.  They typically form around black smokers near continental rift zones.  SMS are know to hold economic concentrations of Gold, Copper, Silver, Lead, Nickel and Zinc.

BlackSmokerHiRes
BlackSmoker

Black smokers create SMS deposits by expelling superheated sea water that is rich in metallic elements.  Cold sea water is forced through the sea floor by the pressure created from the weight of the water column above it.  The water is then heated to temperatures in excess of 600°C when it is brought close to the magma that lies below.  The heated water becomes acitic and carries with it a high concentration of metals pulled from the surrounding rocks.  Once the hot, metal rich, water comes into contact with cold sea water the metals crystallize and deposit on and around the black smoker.

Mining

Large scale ocean floor mining has not taken off yet.  Attempts have been made since the 1960s and 70s  but failed due to technological and financial challenges.  Small scale shallow ocean mining has been a lot more succesful in recent years.  A great example is the popular TV show Bering Sea Gold.  The miners in Nome Alaska are using modified suction dredges to comb the sea floor in shallow waters.

Currently proposed sea floor mining ideas are essentially super high-tech placer mining.  They involve ways to dig through the surface layers of the ocean floor, bring the material to the surface and ship it to a processing facility.  Its a lot like dredging but on a massive scale.  As mentioned above, normal hard rock deposits also occur under the ocean but no plans have been proposed to build open pit mines under the ocean.  That would involve all the challenges of building a mine on land with the added complexity of operating under the ocean.

Why is ocean floor mining possible now when it wasn’t 20 years ago?  The answer comes down to one word, robots.  The world of under water mining is the domain of autonomous drones and human controlled ROVs.  Robot submarines are nothing new, they have been around since the 70s and have been used to explore depths of the ocean that are very difficult for humans to get to.  UUVs or unmanned underwater vehicles are a little bit newer, they are basically an autonomous version of ROVs.  Ocean mining robots have just been invented and share a lot of the technology used in these devices and they look like something straight out of science fiction.

cutter
The Cutter

The first deep sea mining project is currently being developed off the coast of Papua New Guinea.  The project is called Solwara 1 and is being developed by a Vancouver BC mining company called Nautilus Minerals.  Solwara 1 is a copper/gold SMS deposit with estimated copper grades of 7% and gold grades in excess of 20g/t and an average gold grade of 6g/t.  The property sits at about 1600m depth.

Nautilus has developed a suite of underwater mining robots and a complete system to mine the precious metal and bring it to shore.  There will be the bulk cutter pictured above, an auxiliary and a collection machine.  Please take a moment and marvel at these amazing achievements of engineering.

Transporter Bridge TeessideTransporter Bridge Teesside
 After the robots dig up and collect the ore a custom designed Riser and Lift System (RLS) will bring the material to a giant ship that acts as the mine control center dubbed the Production Support Vessel (PSV).  The RLS is basically the world’s most powerful suction dredge.  It’s pretty complex, this is the description on the Nautilus Minerals website:

The Riser and Lifting System (RALS) is designed to lift the mineralised material to the Production Support Vessel (PSV) using a Subsea Slurry Lift Pump (SSLP) and a vertical riser system. The seawater/rock is delivered into the SSLP at the base of the riser, where it is pumped to the surface via a gravity tensioned riser suspended from the PSV.

Once aboard the Production Support Vessel the mined slurry will be dewatered and stored until anouther ship comes to take the material on shore for processing.  The removed sea water is pumped back down the RALS which adds hydraulic power to the system.  Pretty cool stuff!  Check out the video below for an visual explanation of how it will all work.

Exploration

Ocean floor prospecting is not a good place to be gold panning or hiking around with a rock hammer.  It is also difficult to take usable photos due to poor light and lots of debris in the water.  So how do you explore for minerals in the ocean?  Geophysics and robots.

Geophysical exploration is not unique to the ocean.  The same techniques are used routinely on land to find every type of mineral deposit.  Ocean geophysics is also not new.  The main workhorse of mining exploration is magnetometry.  Which means mapping changes in earth’s magnetic field using a specialized sensor.  The technique was actually developed to detect enemy submarines during World War II.  Since then magnetometers and the science behind them have evolved into accurate tools to measure geology.

I’m using a proton precession magnetometer in the photo below.  There is some sample magnetometer data on the left.  Mag maps look similar to a thermal image except the colour scale represents magnetic field changes (measured in nanoTesla) instead of temperature.

Walk Mag in ActionSampleMag

Magnetometers are excellent tools for ocean mining exploration.  They are not affected by the water and are excellent at detecting metallic anomalies.  There are now underwater drones that can collect ocean magnetometer surveys without the need for human intervention.

Autonomous Magnetometer Drone
Autonomous Magnetometer Drone

Other geophysical techniques have been used in ocean mineral exploration.  Electomagnetics (EM) techniques are also great tools for exploration under water.  EM works in a similar way to magnetometry except that they emit their own source.  Conventional metal detectors are actually a small version of an EM system.  While mag passively measures Earth’s magnetic field EM measures the difference between a source and received pulse.  EM also works great for discovering metallic anomalies and is being incorporated into autonomous drones as well.

There are other types of ocean geophysics such as seismic refraction which uses a giant air gun to send a sound wave deep into the crust and measures the response on floating hydrophones.  Sonar and other forms of bathymetry can provide detailed maps of the ocean floor.  Bathymetry techniques can create imagery similar to LiDAR that is used on land.

Sample Bathymetry
Sample Bathymetry

Ocean mining is just in its infancy and some really cool technology is being used.  Advancements in the robotics have allowed mining and exploration to be completed without a person having into enter the water.  As technology advances further we will be able to explore vast areas of the ocean floor and discover immense mineral reserves that are presently unknown.  It is estimated that we have only explored about 5% of the ocean floor, who knows what we’ll find down there?

Share Button

Hunting for Diamonds in the Arctic

Hunting for Diamonds in the Arctic

Back in 2010 I had the opportunity to work on a diamond exportation program in the Canadian Arctic.  The camp was called Credit Lake and was located near Lac de Gras in the North West Territories.  The Lac de Gras region was the epicentre of the 1990s diamond rush after the discovery of the Point Lake kimberlite pipe by Chuck Fipke.  Today there are three operating diamond mines in the region Diavik, Ekati, and Snap Lake.

rawDiamond

Diamonds are found in volcanic structures that are called kimberlite pipes.  These are volcanic events that take place very rapidly.  Most volcanoes take thousands or millions of years to develop.  A volcanic pipe can develop and explode in less than a day.  These volcanic explosions are charged by high pressure carbon dioxide and water vapour.  And travel from the below the crust melting through rock at over 100km/h.

CreditLakeLocation

It is important that volcanic pipe events happen quickly if you want to mine diamonds.  The environment where diamonds form is under intense heat and pressure.  Once the pressure is removed diamonds will melt into graphite which is much less desirable.  In kimberlite pipes diamonds are carried to the surface as the superheated kimberlite melts its way through the layers of the crust. When the pipe reaches the surface it releases its energy in a huge explosion and then quickly cools.  The diamond crystals do not have time to melt, they cool with the rest of the pipe and stay in place.

Diavik Diamond Mine
Diavik Diamond Mine

The volcanic events that created the North West Territory kimberlite pipes took place millions of years ago.  The surface has been subjected to many ice ages over the years and different continental ice sheets have scoured the surface like a bulldozer.  To find a pipe today you look for the debris field left behind as the top of the pipe was scraped by ice sheets.  As the glacial ice sheets retreated they left behind a trail of ground up rock and indicators for diamonds if you’re lucky.

Credit Camp

My first stint at the camp was for six weeks in 2010.  We were searching for diamonds as well as nickel.  My role was to analyze pulverized rock samples from an R/C drill as well as preparing samples for assay and general exploration work.  I returned in 2013 to conduct geophysical surveys including ground (snowshoe) magnetometer and HLEM.  Both trips were in early spring when the temperature in the Arctic ranges from -50°C to -10°C.  Show storms were frequent and the ice on the lake was five feet thick.
TwinOtter

The camp is extremely remote, approximately 300km North of Yellowknife,NWT.  Everything is brought in by ski plane or helicopter.  In addition to exploration work we had to work together to keep the camp running.  When a plane would arrive we would all pitch in to get the groceries, diesel drums, and any other supplies off the plane and into the camp.  The same was true for getting water out of the frozen lake for showers, laundry and the kitchen.  Water is always a challenge in remote areas when it is extremely cold.


While I was at the camp we experimented with several different water gathering techniques they all had their merits.  What we ended up doing was using a chainsaw to cut out a section of the lake ice.  Then used an ice auger to drill the final few feet (see video above).  We used a snowmobile toboggan to transport pails up to the reservoir inside the kitchen.

To travel to and from the locations we were exploring we took a helicopter.  We had a Eurocopter Astar B3 to shuttle people and move the heli-portable drill around.  We also had a couple of snowmobiles and a GMC pickup truck that had tracks instead of wheels.

A Star GMC Track Truck

The RC drill is a super light weight drill that produces crushed rock instead of core.  The RC stands for Reverse Circulation.  The drill is air powered and behaves like a giant hammer drill, like the kind that you use for masonry work.  The air returns from the bit carrying the rock chips to a hopper where samples can be collected.  The advantage of an RC drill is that it doesn’t require water and breaks down for rapid transport.  RC drilling is quicker and less expensive than diamond drilling.

RC Drill in Action

100_1316

After field samples were collected I conducted several tests on them inside our field lab.  We had an X-ray fluorescence (XRF) analyzer which is a pretty cool instrument.  It bombards the sample with high energy X-ray radiation and the atoms re-emit photons which gives information about their structure.  XRF basically gives you a rapid geochemical assay.  I also conducted magnetic susceptibility tests and identified the lithology of chip samples using a microscope.

Field Lab

The accommodations were first class.  At least as far as small remote exploration camps go.  We stayed in Weatherhaven dome tents which are heated by diesel stoves.  As long as there is fuel in the stove you will be comfortable in any weather conditions.  The stoves are prone to issues though and use half a drum of diesel per day when its super cold.  Our beds are constructed out of 2×4 lumber that was flown in and everybody uses a sleeping bag for bedding.  This camp was not a “dry camp” which means that alcohol was allowed.  That is a huge plus when you’re stuck in the middle of nowhere for six weeks.

My houseCamp Tents

The high latitude makes for great northern lights viewing.  That is actually my favourite thing about the Arctic.  Interestingly the mechanism behind the glow of the Aurora Borealis is the same as the XRF machine.  The molecules in the upper atmosphere are excited by a stream of radiation from the sun called the solar wind.  When molecules are excited they reach an unstable electron configuration and rapidly release a photon as they return to a stable state.  The different colours are due to different molecules being excited such as high altitude ozone, oxygen and nitrogen.  The phenomenon is difficult to photograph but here are some of my best shots below.  The best photo in the world doesn’t compare to seeing it in real life though.

OLYMPUS DIGITAL CAMERA

ChopperAurora

The days out in the field can be pretty tough when the temperature drops.  We built a survival shack that would travel with the drill.  Other than that we were fully exposed until the helicopter arrived at the end of the day.  The survival shack also made a great place to have lunch out of the wind.

Credit lake April 031 Credit lake April 041

In addition to drill sampling I conducted geophysical surveys to identify kimberlite pipes.  We used two types of geophysical survey, magnetometer and HLEM.  Magnetometer or “Walk Mag” is a sensor that measures changes in Earth’s magnetic field in very high precision.  As you pass over different kinds of rock the sensor will record minute changes in the magnetic field.  Once the survey is complete you can produce a map that looks like a topo map except that the you are showing magnetic field instead of elevation.  Click here for a sample of a magnetometer map.  Kimberlite pipes stick out as an anomaly because they have a different magnetic signature to the surrounding rock.  You have to use the old school snow shoes because any metal will mess up the readings.

Walk Mag in Action
Walk Mag in Action

HLEM (Horizontal Loop Electomagnetic) works in a similar way except that there are two parts to the system.  One provides a source field and charges up ore bodies.  The receiver records the response signal from the rock.  HLEM actually works the same way as a metal detector just on a larger scale and records actual data.  The instrument is from the 1980s and is very uncomfortable, fortunately in the winter you are wearing lots of clothes.

Maxmin 1 Maxmin 2

I have always enjoyed working in the Arctic.  Its not for everyone though.  It is insanely cold in the winter and the summer has a lot of bugs.  The wildlife is breathtaking I have seen Muskox, Wolverines, Caribou, different coloured bears, Narwhals, and other wildlife that you cannot see below the Arctic Circle.  The Northern Lights shows are simply amazing.  The people are different too.  This kind of work attracts a different breed, those who are willing to travel to remote areas.  Arctic explorers all share a strong sense of adventure.

 

 

Share Button