Different Types Of Mining Processes

Mining has become a controversial industry because of its “devastating” effect to the environment and the ecosystem. However, it has contributed so much to civilization that without it, we could never be where we are today in many aspects.

There are two basic methods of mining. These are the surface and the underground mining processes:

1. Surface Mining

This involves the mining of minerals located at or near the surface of the earth. This encompasses at least six processes and these are:

• Strip Mining – this involves the stripping of the earth’s surface by heavy machinery. This method is generally targeted at extracting coal or sedimentary rocks that lay near the earth’s surface.

• Placer Mining – this involves the extraction of sediments in sand or gravel. It is a simple, old-fashioned way of mining. This method is generally applicable to gold and precious gems that are carried by the flow of water.

• Mountain Top Mining – this is a new method which involves blasting of a mountain top to expose coal deposits that lie underneath the mountain crest.

• Hydraulic Mining – this is an obsolete method that involves jetting the side of a mountain or hill with high pressure water to expose gold and other precious metals.

• Dredging – it involves the removal of rocks, sand and silt underneath a body of water to expose the minerals.

• Open   Pit  – this is the most common  mining  method. It involves the removal of the top layers of soil in search for gold or buried treasure. The miner digs deeper and deeper until a large,  open-pit  is created.

2. Underground Mining

This is the process in which a tunnel is made into the earth to find the mineral ore. The mining operation is usually performed with the use of underground mining equipment. Underground mining is done through the following methods:

• Slope Mining – it involves the creation of slopes into the ground in order to reach the ore or mineral deposit. This process is generally applied in coal mining.

• Hard rock – this method uses dynamite or giant drills to create large, deep tunnels. The miners support the tunnels with pillars to prevent them from collapsing. This is a large-scale mining process and is usually applied in the extraction of large copper, tin, lead, gold or silver deposits.

• Drift mining – this method is applicable only when the target mineral is accessible from the side of a mountain. It involves the creation of a tunnel that’s slightly lower than the target mineral. The gravity makes the deposit fall to the tunnel where miners can collect them.

• Shaft method – this involves the creation of a vertical passageway that goes deep down underground where the deposit is located. Because of the depth, miners are brought in and out of the  pit  with elevators.

• Borehole method – this involves the use of a large drill and high pressure water to eject the target mineral.

These are the basic methods used in the extraction of common minerals. There are more complex systems, but still, they are based on these fundamental processes.

Gold Mining In The Carolina Slate Belt

The Carolina Slate Belt is a gold-wealthy strip from Virginia, south through North and south Carolina and ends up in Georgia. Numerous rivers and streams in this area  contain placer gold deposits. Although most people in the US knew of the gold  as a result of the gold rush California, the first gold discovery in the United States in North Carolina was within the Carolina Slate Belt. Gold was first discovered in the United States in 1799 in the Little Meadow Creek in Cabarrus County, North Carolina. 

Although this discovery was not as much attention as the discovery California , In fact most of the experienced gold miners who moved to California, during the California Gold Rush had honed their skills mining areas along the Carolina slate belt. After the first gold find some other discoveries in shale and thus more gold mines were developed. 

Geology In Carolina Slate Belt 

The Carolina Slate Belt majorly composed and derived from rocks that were deposited from volcanic eruption on the surface of the Soil and then sedimentation. The slate is thus characterized by low grade metamorphism that a Large number of rocks is a slaty cleavage here.

Inside Piedmont for the most part consists  and often occur from metamorphic intrusive rocks such as various types of gneiss. The whole region Piedmont is underlain at a depth of Approximately 20 km from a region, the seismic waves reflected emphatically.

This area is often regarded as a series of faults along the upper part, including the uncovered portion of Piedmont, moved westward over a number of completely unknown rocks. The error may twist upward toward the west and rise to the top as one of the various thrusts in the Appalachian Mountains.

The slate is made up of low grade metamorphosed volcanic and slate cleavages. The mountainous Piedmont of North Carolina isolates the Triassic-Jurassic rift basin and the level Coastal Plain from the hilly Blue Ridge and Appalachians. 

The coastal plain consists of Mesozoic-Cenozoic sediments created when the North Atlantic got to be wider and the Triassic-Jurassic rift basins of sedimentary rocks in the plan during the opening of the Atlantic Ocean formed. The Raleigh Belt and Eastern slate belt containing rocks Love that of Piedmont. However, these are only exposed to the east of the Triassic-Jurassic basins and their connection to the Piedmont is not entirely clear.  

The Piedmont can be divided into two parts, the western and eastern areas of both the two very different rock suites. The eastern part is the Carolina Slate Belt, while the western part is often referred to as the interior of Piedmont.  A number of geologists often combine the Carolina Slate Belt and Inner Piedmont, what is commonly known as the Carolina Terrane 

Two of the most important gold mines in the Carolina Slate Belt included :

Haile gold mine
 

The mine developed from a gold deposit, which was discovered in 1827 on the farm owned by Benjamin Haile in Eastern Lancaster County near Kershaw, South Carolina. The mined operated until the early 20th century operated when the gold deposits originated. This mine was one of the most productive gold mines during the years. 

The Dorn Mine

This is another Large mine in the Carolina Slate Belt. The mine is located in McCormick County, South Carolina. Gold in the mine was first discovered by William soon began Burkhakter Dorn in 1952. The mining at the mine after Dorn and lasted more than 120 years. The slate has several other mines quite a significant amount of gold. In fact, most major gold mines in North and South Carolina Located on the Slate. 

There are numerous other smaller placer mining are found throughout Virginia, North Carolina, South Carolina, and Georgia. All of the gold-bearing areas most rich within these states are found in the slate belt.

Mining has been done in this area for over 200 years, but there are still Nice amounts of gold in the streams and rivers in the Carolina Slate Belt are found.

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Source Of Gold Ores

Gold and silver metals are obtained from a variety of different types of rock ores. Most people think of gold nuggets constitute the source of the gold. But the reality is very few gold derived from the nugget. Nearly all newly mined gold comes from ores from natural hard rock mining, fine gold grains, even microscopic particles. 

Gold widely found in nature, although it is one of rare metals. It often happens gold which known as the native metal encased within a mineral such as quartz. And historically gold the most productive, occur in the vein deposits. Currently these widespread deposits give much of the world gold ore. 

The element gold ores in nature occurs even mainly in the form of native gold, In various gold ores, original gold mineral content commonly occurs, fine mineral particles and small contained within sulfide minerals such as pyrite.

Iron pyrites a very common mineral associated with gold, but it also serves as a reducing agent. Therefore, if gold is found enclosed in pyrite, it is always free gold and not as some kind of gold sulfide. Gold also sometimes in chalcopyrite, galena and arsenopyrite and stibnite, but not as one is found in such quantities as may be found in pyrite. Other minerals such as sphalerite, pyrhotite, magnetite and hematite sometimes carry little amounts of gold as well. 

Gold also comes as Telluride as Calaverit. Common gangue in gold ores include quartz, fluorite, calcite and pyrite, but many others can be found in smaller amounts

Gold Ore Minerals :

The most prominent is pure gold – The most common the native gold contains a Little amount of silver, copper, platinum, etc. 

Telluride minerals are the most common minerals that significant gold in their makeup. These include:

• Petzite (Ag, Au) 2, Te,
• Hessit (Ag2Te)
• sylvanite (Au, Ag) Te2
• Calaverit (Au, Ag) Te2
• Krennerit (Ag2Te, Au2Te3)
• Nagyagit ( Au2, Pbi4, Sb 3, TE7, S7). 

The gold containing sulphides and tellurides, are primary formation from gold ore, although auriferous chalcopyrite could be formed by secondary enrichment process.

Native gold can occur in the primary, secondary enrichment or oxidized zones. The tellurides, which are usually associated with pyrite, are widely used, though not so often, but not always recognized; in fact, some of the miners they are mistaken for sulfides  

Common types of gold ores

Gold deposits are often classified according to their association. 

1. Of these can be cataloged as quartzose.

This means that the gangue mineral is acid, that is, quartz and fluorite which may be very abundant or the other gangue minerals of the alkaline soil group. Not infrequently, it seems varies pyrite and limited amounts of chalcopyrite and galena within quartz quantities. These are free milling ores.

Through a free milling ore it is meant that the rock does not require roasting before the gold can be recovered therefrom. Dry ore is the term that is often used for this category. 

2. Copper ores containing gold ore mineral

These are widely used in the United States and much of the chalcopyrite is gold bearing. This auriferous copper ores are particularly abundant in Colorado, Utah, Montana and British Columbia. They are also in Gold Hill, North Carolina and in Canada to Newfoundland. 

3. The class of gold ore is auriferous lead ores.

The proportion of lead in these rocks is large and the gold content is often low. They are refractory ores such as copper ore. The refractory ore is a meant requires roasting before extraction processing. The heavy sulphides as copper, lead and antimony require this method of treatment, that is the condition of the gold in the mineral will not allow of its immediate capture with most recovery systems.

4. gold ores comprises the gold-telluride group

The gold telluride ores occur accompanied by other tellurides with silver, lead and antimony or as native gold accompanied by other tellurides.  These ores are often sent directly for the treatment of smelters. 

5. Type of disseminated ore.

They are often low in grade, but present in very large numbers. They fill large fracture and fault zones or replace certain geologic horizons. They are the result of the circulation of large amounts of heated water deep underground.

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Drill Testing To Sample Gold Deposits

Test process drilling for gold is an important step in the every prospecting and gold mining industry. Test drilling is a step that is used continuously to obtain samples of bedrock in the land of gold mining project. The sample is then tested to determine whether it is gold in the project area in mining and to estimate the amount of gold that can be mined in the area. 

In the process of drilling testing can produce a variety of results sample, because each gap can occur various kinds of different types of rocks and soils, The process of drilling test is a step that most highly effective to get the test results of rock in the ground in estimating the amount of gold ore deposits in the area which will do the mining.

Drilling is an absolute necessity to assess metal ores prior to the process of exploitation in an extensive mining operation. Drilling can be done for all large-scale mining, before the open pit mine development, or for the assessment of large commercial placer mines. 

Preliminary Prospecting Works In Test Drilling

Before test drilling for gold, there are several steps that can be done early, it is made to prospecting works. Often the area to test can bushes, hard terrain or other obstacles drilled, which may influence the outcome of exploratory drilling. It is important, therefore, it will be handled first.

One step that can be used is by ridding the area which will be conducted test drilling. This can help reduce the amount of land the ground which will done testing on drilling,thus support and make to be effective the test holes are drilled. 

Drill testing

In the process of test drilling in gold mining is intended to determine whether the area has gold potential which can be used for large-scale mining.This is very helpful in determining the amount of gold deposits
and grade gold contained in the soil in the area that will be in mine.

Test drilling can also specify the information that is significant of the general geology of the rock structures that exist in the soil at the prospect area, the geochemical structure and other information from other minerals besides gold deposits existing in the test drilling area 

The pattern of test holes, the distance and the number of test wells is mineral determined by the geometrical alignment of the drill, the geochemical composition of the area and the distribution of the target.

For most in scale test drilling in mining area is often gridded out into small grids that can determine the number of holes to be drilled. Sometimes in the drilling process is done in a manner soil formation such as rifts, ditches, river basins or even valleys. 

In most of the tests for the drilling of gold speed and cost are important factors that are considered by geologists.

If in the process the first step is successful, then to get a drilling method that is more accurate in determining the mineral content of gold or may be in the process of the most extensive can be implemented

Some of the methods most commonly used test holes, you can use includes hand drilling, rotary drilling, percussion drilling and diamond drilling. 

The significance of the test drilling for gold

test drilling is to enhance the importance of prospecting before a mining operation, and drill testing is one of the methods most commonly used for sampling.

Albeit with very expensive, it takes some of the risk and guesswork out of the mining process and an estimate of how much gold there is in the area

The type of drilling specifies the device to be used. 

Hand Drilling

This is carried out in at a little place for little operations. Hand drilling done by using a manual hand, the phase required prior training stage, as sample tubes and augers. These drills can not penetrate bedrock and thus limited in its application entirely.

Variety of hand drilling tools can be used for hand drilling, but hand test can only for little gold mining drilling.The advantage of the hard drilling reduced cost of major methods, and this may be the best method for individual miners who lack the resources for greater exploration.

 Percussion Drilling

This type test drilling where the drilling equipment can be used to enter into the bedrock up to a depth of approximately 10 meters. Percussion drilling is drilling that uses compressed air drilling equipment, this makes lebihh far stronger than using a hand drill.There is also drilling using large air drilling equipment ,which can be used in complex drilling in the mining area.

Rotary Drilling

Rotary drilling is drilling relatively expensive yet very easy to use in a variety of conditions. In the drilling process using a ring and an air compressor in the process of drilling holes to be tested. With the true tools and skilled workers, this type of exploratory drilling takes the least time of all available drills. The drill may obtain samples from between 20 and 100 foot holes. 

Diamond Drilling

This is the most versatile drill testing method that can use. The machines used for this type of drilling gets superior most samples since it can drill deep and at a certain angle and conditions.

In most cases, drills are used herein, can be powered by electric engines, gasoline, diesel, and even air. However, the process can only slow and very expensive in practice and thus it is used only for complex projects that require extensive drilling.

This Video  from Hellix Ventures Inc. - Margarita Gold Drill Program

Why To Invest In Silver

Is silver a good investment? The answer is ‘yes’. Like gold, silver is a safe investment that offers an effective value against inflation and adverse economic conditions, apart from wealth creation.

Unlike currencies, the value of silver does not fall in real terms any time. However, before decide on how to ways invest in silver or where to buy silver, we should know why to invest in silver.

Here’s a look at the pros and cons of silver investing:

 Advantages For Silver

1. Returns. 
Though silver is almost 17 times more abundant in nature than gold, however silver it is more scarce in circulation. According to some estimates, the combined sovereign gold holdings by various treasuries in the world are more than the total mined silver available.

Historically, silver has outperformed gold in terms of returns and it is truer in present times than ever before. Over the last two decades, the returns on silver have been almost three times that of gold.  Since 2009, silver price has increased 87% with over 630% returns, while gold price increased 30% with over 250% returns.

 2. Demand. 

The demand for silver is not driven by economic condition alone. It has a large use in industry and in recent years that has been the major factor for silver’s price rally. Currently, almost half of the total demand for silver is industrial.

Most of the silver that is used in industry cannot be extracted and recycled due to various reasons, implying that silver is being ‘consumed’ in manufacturing. Such demand is likely to continue pushing silver higher in the future.

3. Affordability.
Known as ‘poor man’s gold’, silver is a highly affordable precious metal for all practical purposes. The gold to silver ratio is one of the most watched metrics in the precious metals area. This ratio has been fluctuating over years.

Even at current silver peaks the ratio stands at around 31, indicating that gold price is around 31 times that of silver. Therefore, affordability combined with returns makes silver a winning investment option.

4. Liquidity
Like gold, silver has high liquidity and is easily traded in various forms all over the world. In the long term, silver was used as a currency in different parts of the world and enjoys similar recognition even today.

5. Alternatives.
There are various types of investments in silver that you can choose as per your requirements. These include bullion coins, collector’s coins, bars, silver rounds, jewelry, junk silver, scrape, mutual funds, Exchange Traded Funds (ETFs), futures, options, certificates, and silver accounts.

Disadvantages

1. Bulk
Due to its low pricing, an equivalent amount of investment in silver is much heavier and requires more storage space than gold. This adds to transportation, insurance and storage costs for silver.

2. Maintenance.
Silver gets oxidized readily, losing its sheen to a blackened appearance. Some of the premium that is paid at the time of buying a piece of silver is related to its appearance. May lose out on such premium on your tarnished holdings at the time of selling.

Therefore, it is very important to retain your physical silver in pristine condition. Bullion coins and certain numismatic coins are often available in protective, covering that protects them from oxidation. However, silver bars are exposed and face a greater risk of tarnishing.

3. Taxation.
Unlike gold, silver is subject to taxation in most of the nations, either as capital gains tax or as value added tax. The tax rates in various countries range between 7% and 22%.

4. Instrument-specific drawbacks.
Individual forms of silver investments have different types of disadvantages. For instance, futures are subject to inherent riskiness of the metal and markets. Another example is jewelry, which is unprofitable because its price includes crafting cost that fetch no value at the time of sale.

This is Video How to invest in silver  

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