How gold is mined depends on the deposits. Lode deposits are concentrations of gold found in solid rock. If the gold-bearing rock is located at the earth's surface, the mining company will use open-pit techniques. First, miners drill a pattern of holes, which they then fill with explosives. Gold is found both close to the surface of the Earth and underground, mixed in with other metals such as copper, silver and lead. Where the gold is located will dictate what type . Yet mining the ore is just one stage in a long and complex gold mining process. Long before any gold can be extracted, significant exploration and development needs to take place, both to determine, as accurately as possible, the size of the deposit as well as how to extract and process the ore efficiently, safely and responsibly.
Modern gold mining processes are largely the same techniques used in gold mining for hundreds, if not thousands, of years. The modern processes for mining gold use larger equipment and more refined techniques, but essentially it still the same principles as has always been used. Gold mining methods and techniques. Simple, easy ways to find gold and mine it. Placer gold mining streams, rivers, gold panning, sluice boxes and. How gold is mined depends on the deposits. Lode deposits are concentrations of gold found in solid rock. If the gold-bearing rock is located at the earth's surface, the mining company will use open-pit techniques. First, miners drill a pattern of holes, which they then fill with explosives. Gold is found both close to the surface of the Earth and underground, mixed in with other metals such as copper, silver and lead. Where the gold is located will dictate what type . Yet mining the ore is just one stage in a long and complex gold mining process. Long before any gold can be extracted, significant exploration and development needs to take place, both to determine, as accurately as possible, the size of the deposit as well as how to extract and process the ore efficiently, safely and responsibly.
How gold miners find, mine, extract and leach gold ore into Gold Bars for investment.
WHAT EXACTLY IS gold supply? asks Julian Murdoch for Hard Assets Investor.
That is, where does all the Gold Mining happen? How does it work? And how do schneider mining technology, the investor, parse bullion from all the senseless jargon found in the annual reports of leading mine companies?
Well first, you've got to find it. Gold is everywhere on Earth, but it's not commonly found in significant concentrations. The Earth's crust contains approximately 0.004 grams of gold per ton, and there is even a lot of gold in saltwater, how is gold mining. Concentrating such trace amounts just doesn't make economical sense, however.
To make money – or at least have a decent chance at it – you've got to look mining lighting led you can find gold in your local streambed (especially if you live in California or Nevada), those placer deposits – places where valuable minerals have naturally accumulated over time – aren't typically what the commercial mining companies are looking for. It's not a reliable enough source of steady gold to justify large investments.
Instead, they look for relatively high concentrations of gold in the earth, concentrations which can be mined and refined into pure bullion.
Gold how is gold mining found both close to the surface of the Earth and underground, mixed in with other metals such as copper, silver and lead. Where the gold is located will dictate what type of mining process is used to retrieve it – and what costs will be associated with it.
It all starts with the geologists. By studying the type and formation of the rocks in a region, how is gold mining, and taking samples, geologists direct where mining companies need to explore. To determine what exactly is at a site, numerous ore samples are taken, called "diamond drill cores", using (as the name suggests) drill bits tipped with industrial diamonds to create an ultra-hard cutting surface.
These core samples are 3.5 cm in diameter and can be the length of a football field. By examining them carefully, geologists can tell engineers exactly where the ore they want is located and how it is combined with other metals and rock. After that, it's up to the engineers to figure out how to get to it.
Two critical stats from the core samples are the grade of ore and size of the find. This is where the terms "proven and probable reserves" or "measured and indicated reserves" come from when we're digging into annual reports.
- Probable reserves are areas where gold is known to exist – but where extraction may or may not be economically or technically viable;
- Proven reserves are just that: The geologists can see the gold in the core samples, and the engineers are positive they can get at it.
- Measured and indicated reserves are terms that are not how is gold mining by the US Securities and Exchange Commission, but are required by the Canadian government.
When you look at the annual report of a company such as Barrick, it will show the "proven and probable" numbers as well as the "measured and indicated" numbers to satisfy the laws in the countries in which they operate and where their stock is traded.
Either way, the mining safety issues give the companies' best good-faith estimate as to the amount of total gold that could be mined from a given area over the life of a mine. It does not guarantee the gold will be mined, or even that it can be mined, how is gold mining, but it holds out the possibility.
The higher the grade of ore, the more gold present and the more cost-effective it will be getting to it. As in most businesses, cost-effectiveness is the name of the game, and in mining, that means controlling how you run your mine.
The open-pit mining process – as illustrated by Mine-Engineer.com below – is used when the gold is located close to the surface and the site makes an open pit economically and environmentally feasible. It is exactly what it sounds like – a giant hole dug in the ground with roads leading around and up to the top of the mine to facilitate getting machinery in and getting ore out how is gold mining the mine.
Excavation is done with explosives and heavy machines – both of which have high costs associated with them. (Diesel fuel alone can account for 25% of a mine's costs.)
Each ton of ore that is hauled out of a good pit mine may contain about a tenth of an ounce of gold. With gold at, say, $900 an ounce, that makes a ton of ore worth $90, tops. Considering that the huge trucks used at some mines can hold up to 300 tons or more on each run, how is gold mining truckload of ore coming out of the mine can be worth around $27,750. Of course, reality doesn't really work that way: Some loads are richer than others, and many turn out to be literally worthless.
When an open-pit mine doesn't make sense because the gold is located much farther underground, how is gold mining, or other concerns limit the mining, an underground mine is used.
Shafts are dug with tunnels branching out, leading to the load deposits. The mining process is straightforward, yet technical and a lot of hard work – you have to drill holes for explosives, set off those explosives and then haul out all of the resulting blast debris. The days of picks, shovels and wheelbarrows have given way to explosives, muck machines and carts – though I'm sure there is a lot of back-breaking shovel work involved as well.
The cash costs associated with underground mining include not only similar things as used in open-pit mining (explosives, diesel fuel, machinery and labor) but also electricity. Without electricity, there is no air underground, and no transportation of workers, machinery or ore in or out. To meet this need, some companies (such as world Gold Mining No.1, Barrick) have situated solar or wind farms close to their mines to help ensure a steady supply of this important resource.
Remember: Many gold mines are located in difficult-to-reach areas, where reliable power is a long-off dream. And once the ore has been liberated from the ground, the gold will then need to be extracted from the ore.
The processing consists of taking the big pieces of ore and making them smaller, until it reaches the consistency of beach sand. At this point a cyanide solution is added to the mix and milled further into a muddy, watery mix.
- A weak cyanide solution combined with air dissolves gold, freeing it from the other rock and metals in the ore;
- Once cyanide dissolves what gold it can into the solution, the fluid is pumped off while the remaining solids are transferred into agitation tanks where the remaining cyanide continues to dissolve the remaining gold into the water with the help of air bubblers;
- The heavier materials sink to the bottom and the pregnant solution is combined with fluid and zinc to precipitate the gold out of the solution.
- This process, called cyanide milling, is fairly efficient – recovering 95% to 98% of gold from the ore. It can be done economically using ore with less than one gram of gold per ton (depending, of course on the Gold Price).
When lower-cost extraction is needed, how is gold mining leaching is used. Ore is piled in a lined, prepared area and then treated with dilute cyanide. As the solution works its way down through the pile, gold is dissolved and drains to the bottom.
The solution is collected, the gold precipitated out and then refined. The drawback to heap leaching is that not only is it a lengthy process, but only 65% to 85% of the gold present in the ore is extracted using this process.
Refining takes place in the smelter where the gold and a chemical cocktail called flux – magnesium dioxide, fluoride, silica flour, borax and sodium nitrate – are combined and heated to 1,600 degrees Celsius. This process separates the gold from impurities (slag) so that it can be poured into bar-shaped molds. The resulting bars are 80% pure. Further refining purifies the gold to 99.5% fine or better – the Good Delivery standard for wholesale gold shipments and investment.
After all how is gold mining the processing of the ore and extraction of gold, the companies are left with a lot of leftovers – the tailings: ground rock and processing by-products that contain a lot of nasty things like mercury and how is gold mining. Companies store these tailings in surface containment areas or use them as backfill in mined-out voids where possible.
Between the explosives, caustic chemicals and huge machinery, is it any wonder that gold companies spend a lot of time talking about safety, environmental concerns and oil prices in their annual reports? But for shareholders, of course, what matters is the all-in costs: how much it takes to remove gold from the ground and prepare it for sale.
This cost-per-ounce varies by company, depending on its mix of mining and its operational efficiencies. For Barrick, gold cost $443 per ounce to pull out of the ground in 2008. That compares with an annual average Spot Gold price of $871 an ounce.
Companies can't really influence the price of gold much, but they can contain their costs. So conserving energy, locking in cheap fuel prices, negotiating cheap labor, keeping the mines safe and open, controlling waste so as not to pay fines or money on lawsuits – these are the nitty-gritty parts of running a Gold Mining business.
Now that you know a bit more about where those cost come from, you might gain a bit more insight the next time you're reading 28nm bitcoin mining the annual report. Or at least you'll know what makes up the "total cash costs per ounce" accounting line item, which will determine (as much as the Gold Price itself) what profits a company you're reviewing could deliver.
Geophysics & Exploration Instruments | Instrumentation GDDYet mining the ore is just one stage in a long and complex gold mining process. Long before any gold can be extracted, significant exploration and development needs to take place, both to determine, as accurately as possible, the size of the deposit as well as how to extract and process the ore efficiently, safely and responsibly. To Start Your Own Gold Mine may be very profitable activity, just like any other. I am strongly suggesting to read the book Think and Grow Rich - Wikipedia as to. Gold mining news. Explore related Gold articles for more information on the Gold mining industry.
How gold is mined depends on the deposits. Lode deposits are concentrations of gold found in solid rock. If the gold-bearing rock is located at the earth's surface, the mining company will use open-pit techniques. First, miners drill a pattern of holes, which they then fill with explosives. Gold mining news. Explore related Gold articles for more information on the Gold mining industry. To Start Your Own Gold Mine may be very profitable activity, just like any other. I am strongly suggesting to read the book Think and Grow Rich - Wikipedia as to.
When it comes to gold mining, most of us will get our yellow metal by sifting through sands and gravels along rivers and streams. This is called placer mining. It is due to the geological age of the earth that this is even possible. All gold deposits started as hardrock formations...and stayed that way until there were earthquakes, rivers, glaciers, tidal waves and a lot of earth movement which eroded mountains and ground down the rock into it's smallest form; dust. Trapped in all this rock were veins of gold, typically in quartz. These veins were also pulverized down into small pieces in nugget, flake and flour size. Because gold is so heavy, it settles to the bottom of our rivers, streams and any deep depression or crevice. This is where placer mining comes in. When we sift through all this sand and gravel to separate the gold, we are actually looking back at the earth's history. I know, I know, that's nice; now show us a faster way to get at this gold.
The quickest way to reach this heavy mineral is to go deep and that is the hardest thing we could possibly do. Most placer gold is found within 50 feet of the surface of the ground. That's the "easy pickens". It is all the piles of gravels and sand we have to move first before we can reach the heavy nuggets. All this unwanted material is called "over burden" and it is the over burden that will make or break a mine. There are some very rich areas containing coarse gold that travels for miles following the bedrock of the earth, but there are just too many feet of rock and assorted mineral debris sitting on top of it to make it worthwhile to mine. This is just one of the reasons I am developing the deep gold drill to reach these zones of wealth that no one else can reach.
These golden rich layers vary in thickness from 18" down to a thin hair like trace. If we were to trace back to where these layers started from, it would be an intrusive outcropping of very rich veins that have been crudely eroded and strewn across bare rock or been given enough time to settle to bedrock. Glaciers and tremendous earth movements have left these rich zones buried deeply with over burden. California has one of these very rich areas. The surface of which has been the ancient streambeds that were worked in the gold rush of 1848 to 1855 (1849 being the height of this rush). These semi-surface ancient streams were often mined with hydraulic mining techniques. Please keep in mind that these mined areas often had 40 feet of unwanted rock sitting on top of them and were up a mountain side nowhere near water. That is one view of where gold was. The other is the heavy rich layer that sits on bedrock down deep under the earth. Some of these bedrock areas were accessible by miners usually by diverting rivers and digging down to the heavy layer.
Every method was employed to extract the wealth. Gold panning, sluicing, dredging and hydraulic mining were all used to good effect. Some outcroppings of hardrock gold were also found. At the time, crude attempts at crushing this mostly quartz rock were used to try to free the yellow treasure from the parent rock formations.
This crushed slurry was washed into massive sluice boxes and a lot of gold was captured. Using this early method only captured about 70% of this mineral wealth. The rest ended up in huge tailing piles left behind by these stamping mills. Early "worked areas" can be successfully re-mined using the cyanide process for complete removal of all gold still held in the waste rock.
Normally I would encourage a person to pursue these bedrock zones, but not at the cost of your life. Miners in the gold rush of 1858 in Barkerville, British Columbia often "drifted" down to bedrock, extracting huge quantities of coarse gold by tunneling along these rich placer deposits and simply follow the golden highway wherever it went. What isn't talked about too much is the loss of life that happened all too often. Miners were buried by cave ins in their frenzy to get more nuggets. These drifts were only 40 feet down, the depth of gravel sitting on top of most rich bedrock areas starts at 40 feet and goes to several thousand feet.;
You sometimes hear in the news when construction crews drill down on the bank of a river to set pilings for a new bridge and they hit coarse gold just as they hit bedrock. The layer is only 1 - 3 inched thick and can vary in depth down as I already mentioned. This is an all too common occurrence. Sometimes you hear about it but most times it isn't even mentioned in the news.
Other finds are discovered by water well drillers. It is their job to drill holes - everywhere - and they often find gold seams or rich layers as they drill down in search of water. Of course finding it is nice, mining it is another story. When you have 100 feet of mixed rock and sand on a one inch thick gold deposit, normal extraction techniques aren't going to cut it. These rich accumulations are somewhat spread out and do gather in depressions, cracks and crevices. That is why Billy Barker used a technique called drifting and tunneling to follow the paths of gold 40 feet underground. You have to be strong and determined to move that much earth for the narrow band or wealth that lay waiting on bedrock for thousands of years.
When I finish the deep gold drill I don't know if it will be a new method of mining or not. Early results of my prototype are promising. A brief description of the new type of drill is in the Future Gold Mining Projects.
There have only been a few REAL innovations in the gold mining community in the past two hundred years.
1) Suction Dredges:
1) High processing capacity.
2) Much easier than using a shovel.
3) Works under water.
4) Cleans to bare rock.
1) Illegal in many States.
2) It can wreck the environment if used irresponsibly (lay waste to fish spawning area) although most miners use dredges responsibly.
3) You must have a driver at the nozzle end.
4) You can only use it under water.
5) You can't work some rich waterways due to the current and other hazards.
Gold Suction Pumps:
I am a little biased here. I have seen the gold that can be extracted using the Gold Recovery Pump and the Gold Hornet.
There are many scenarios where one of these pumps can multiply the amount of gold you will take home. This type of gold pump has changed the way placer mining is done. It has also changed the volume of yellow wealth you can easily recover in a short time.
Lastly, the other major improvement in discovery and removal of coarse gold has been:
1) Relatively fast.
2) Good at finding heavy large nuggets.
3) Works wet or dry.
4) Don't need a lot of extra equipment.
1) Always seem to need more batteries.
2) Can't easily "look" under water and pockets between rocks.
3) Relatively fragile.
4) Will only detect nuggets on the larger size at any distance of depth.
I am not trashing metal detectors as they definitely have their place, but, as an additional tool in the miners bag and not a main stay unless you are walking in a dry desert streambed for miles. Old water worn gullies and low ancient water ways can contain some real surprises. if you can imagine how much gold is in the centre of a large river, well, picture that same high flow rate on an ancient river that has totally dried up. hence the incredible finds in what appears to be "dry ground".
Whatever your preference for finding and extracting gold, whether it is sluicing, panning, dredging or using a metal detector, there is still a lot of gold to be found out there. Read my write ups like Ancient Riverbeds and High Benches or Gold Mining Northern Rivers and you will see I do my best to reveal new methods to gold mine as well as new areas and places to search for our heavy yellow friend.
Understanding how nature behaves through time and a little geology (in layman's terms) will make our hobby or business an amazing success. before you try to mine anything be a discoverer first. Go where others usually don't (safely). Check for black sand and iron pyrite (bring a magnet). Find a new gold location and stake a claim. Most of all; don't be afraid of checking out new spots.
A Brief Background
Gold can be found free in nature, but, is usually associated with silver, quartz, calcite, lead, tellurium, zinc and copper. Sea water contains approximately one milligram of gold per ton of water.
Gold is the most malleable and ductile of all known metals. One ounce of gold can be worked into a sheet measuring five meters flat. Gold can be flattened as thin as .000127 millimeters or about 400 times thinner than a human hair.
Pure gold is soft and usually mixed with other metals like:
- and palladium
to increase its strength.
The amount of gold in the mix is measured with a unit called a carat. A carat is equal to one part in 24, so a 14 carat gold ring contains 14 parts pure gold and 10 parts other metals.
Gold is a good conductor of heat and electricity as well as being very corrosion resistant. Gold can be used for a multitude of uses such as:
- electroplating conductors
- reflective telescope mirrors
- reflective coating on skyscraper windows
- along with many many more uses.
It has been said that gold is where you find it! Found gold is welcomed by all races and stands the test of time as rarified wealth by all who possess it.
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