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Tuesday, January 24, 2012

Gold Occurrences in Colombia


Plate tectonics found in Colombia.


It doesn’t happen very often, but Colombia was the subject of a whole section in Engineering and Mining Journal (E&MJ) all about the boom in minerals there.  Colombia is the northern terminus of the Andes Mountains that is also one of the last areas in the Andes to be explored for minerals.  Even the author is interested in the goings on in Colombia because his friend Nick is developing a mine that is located between the Pig Pen and the Old Man in the northern Andes.  We have been consulting on this mine for the past year and although it is beyond the range of the internet Nick gives us regular reports on his progress whenever he gets into town.

Colombia has three different distinct areas where gold is found.  One of these areas is in the Andes proper where it is found as epithermal deposits in shear zones.  The area also contains placer gold. The second area is in the Sierra Nevada de Santa Marta Mountains in the northeast of Colombia.  These mountains are not part of the Andes, but rather are a distinct mountain range in their own right that has the distinction of being the highest coastal range in the world at 5,700 meters (17,760 feet).  Although these mountains are reported to contain much gold it is protected by a tribe of Indians that were never conquered by the Spaniards that take a dim view of gold seekers that are after their gold.  The third area is in the Guyana Shield a large group of Precambrian Rocks that are found in the southeastern part of the country where they continue into Brazil, Guyana and Venezuela.

E&MJ considers Colombia as the last frontier of the Andes Mountains because so much has already been discovered in the Andes further south.  Gold is the least of the mineral wealth of Colombia the country is already the home of the largest deposits of emeralds on earth with finds dating back to the days of the Incas.  Colombia also contains coal measures that are largely being exported to Europe.  One company Xstrata produces high grade coal from its Cerrejon mine the largest in Colombia.

Getting back to my friend Nick in his prospecting he has discovered a pegmatite in the part of Colombia where he is prospecting that contains crystals of aquamarine of euclase,   This will show you that much more then gold can be found in Colombia.

Friday, January 20, 2012

Gold Occurrences in South America


Precambrian Cratons of South America


From the Isthmus of Panama to Drake’s Passage South America is a veritable treasure house of minerals including gold.  Found on this continent are some of the great mineral deposits found on earth.  Of all the deposits of minerals the first discovered by modern man was gold when the Incas filled a room with gold ornaments to ransom their Emperor from the Spanish conquistador Pizzaro and his men. Even with this vast treasure their efforts were ignored when their Emperor, Athapulco was executed by the Spaniards.

There are several different gold provinces in South America with the largest being the Andes Mountains reaching from the Panama border to Cape Horn on the island of Tierra del Fuego. The  Sierra Nevada de Santa Marta Mountains are found on the northeast coast of Colombia, the highest point on the Atlantic Ocean at 5,800 meters (19,278 feet) reportedly contain vast amounts of gold that is guarded by the only Native Tribe that wasn’t conquered by the Spaniards; these Indians to not take kindly to gold seekers even today.  It is thought the Sierra Nevada’s are a high volcanic island that was plastered to South America by earth movements in the past.

In eastern South America there are several Precambrian cratons that also are known gold bearers.  These cratons are the Guyana Shield and the South American Platform that in many places are covered by younger sediments.  Many of the sedimentary basins contain gold that was washed down from the mountains or the Precambrian shields as placer gold.

Like other areas that produce gold in the world the deposits are associated with volcanism or regional heat sources whether ancient or recent.  A great deal of the gold found in South America is concentrated along the chain of the Andes Mountains.  More gold is found in the Precambrian cratons of eastern South America.  A separate source of gold is found in the Sierra Nevada de Santa Marta Mountains in northeastern Colombia.

One of the hot spots in the Andes is the northern end of the chain in Colombia where there are several mining companies staking claims or already have active gold mines. It is in the northern Andes where the author has dibs on a gold mine that is just opening. 

Gold is found throughout South America that has already been the home of several historical gold rushes.  From appearances there is a great deal more gold that hasn't been found in South America.

Sunday, January 15, 2012

Gold Occurrences in Central America


Map of Central America

With the exception of Belize gold is found throughout Central America to the extent that the area has become a Mecca for gold seekers.  The big attraction is the chain of volcanoes that reaches from one end to the other going north to south.  Central America is also one of the youngest landmasses on Earth that hardly exceeds 5 million years old.  The lode gold deposits are all epithermal deposits in nature where the gold is deposited in concentric rings around the volcanoes in the many shear zones in the area.

Recently the level of gold exploration in Central America has increased because the region is not well explored and one might say it is under explored. At the present time ounce of gold carries a high price tag combined with the laws of all the nations in Central America that for the most part are pro-mining and exploration.

The very formation of Central America as an island arc of volcanic islands that was in filled by sediments from both North and South America would be enough to form gold deposits.  Most of the lode deposits found in Central America are epithermal in nature associated with volcanism forming in fault and shear zones.  The volcanism is formed by the Cocos Plate being subducted beneath the area west of Central America just offshore.

Several gold mining companies started exploring the area during the late 1990s in the long isthmus that connects the America’s finding the whole of Central America is spotted with high grade gold deposits.  Central America may prove to be one of the premier gold bearing areas on earth.  Success prospecting Central America will prove to be more successful for those companies that strive for community support among the inhabitants rather then the old time methods of dig and run leaving a mess behind.  This will also help them to get exploration permits leading to the development of a mine if it is economically feasible.

Central America is about the size of the Yukon Territory of Canada but contains several countries all of which except one have gold deposits.  The one exception is Belize that does not contain any reported gold deposits.  Throughout most of the area are mining laes similar to those found in Canada meaning overall they are friendly to the mining community.

Now that the price of gold is hovering around US$1,600.00 per ounce has caused a significant number of grassroots discoveries of gold throughout the region.  Central America is a virtual treasure chest of minerals, more then gold is found there.  One nation, Panama is estimated to hold the largest copper deposit in the whole world.  It is not only a miner’s paradise but one for investors too.

Tuesday, January 10, 2012

Gold Occurrences in El Salvador


Coat of Arms of El Salvador


There are several volcanoes located in El Salvador with most of them found in the western part of the country and have all erupted during the Holocene.  It takes volcanic activity to create gold deposits, and that is exactly what has happened in El Salvador.  The heat from the volcanoes has driven the gold out in concentric circles around the volcanoes and is deposited when the temperature of the water drops below 300o C to about 200o C.  Quartz is also deposited at about the same range of temperature so they are often deposited at the same time.

Most of the lode gold found in El Salvador and Central America in general are in the form of epithermal deposits associated with the many volcanoes in the region.  These volcanoes are products of the subduction zone just off the west coast of Central America.  Many of these deposits grade to copper with depth making it possible that the largest copper deposits can also be found in the area.

Although there are little references to placer gold in the country it is reported to be found in most rivers and streams flowing from the interior as placer deposits in the bottom of the valleys.  Like other placer deposits it is found associated with the gravel deposits associated with flowing water.

First there was a gold rush in El Salvador that quickly was followed by the lawyers.  Although gold in plenty has been found in the country its large scale mining is being opposed by community groups, locals and environmentalists.  It seems their concern is mainly the distribution of wealth between the miners and the local population.  As we speak this is a battle moving its way through the courts!

Pacific Rim Mining has a project named El Dorado that is 65 km east of the capital of San Salvador that is presently in an advanced stage of exploration indicating there is 1.4 million ounces of proven resources available and a potential of much more that is the target for the present exploration program.

Mining and exploration is governed by the 1996 law that was last amended in 2001.
This law is administered by the Ministry of Economy’s Department of Hydrocarbons and Mines governs the granting of exploration license as well as exploitation concessions.  This allows the applicant the right to produce and sell valuable products recovered from natural resources within the area of the concession.  An Environmental Impact Study (EIS) has to be approved by the Salvadoran Ministry of Environment and Natural Resources as well as satisfying a number of other conditions.  Once it is granted the law requires that mine construction be started within the next twelve months in accordance with the conditions on the final permit.

Monday, January 2, 2012

Closing a gold mine


An open pit mine.


The formal name for closing a gold mine is mine closure that occurs when the ore extracting activities at the gold mine have ceased, and ushers in the final decommissioning of the mine and its reclamation. This usually entails laying off most of the workers that can have a very significant impact on the community around the mine and the local economy. This is the time that the end of the life of a mine when the majority of reclamation work is completed so as to make the land safe and useful for other purposes again.
In many of the countries where mining activity is prevalent much of the closure planning has not yet been formalized leading to a floor of unintended consequences that have the potential of becoming a sovereign risk if not well managed.
Closure planning is a development in mine closure that continues throughout the life of the mine that usually starts before the mine is ever in production and is an integral part of the mines business plan. The closure plan undergoes periodic updates throughout the time of active mining, and incorporates a final decommissioning plan for the mine. The Australian model for my enclosure is also followed in many other countries with this model being the standard.
Most miners follow a progressive reclamation plants throughout the life of the mine that reduces the reclamation burden on the mine when it is finally closed.
There are two types of mines that require closure one of them is the open pit mine it is usually closed by a special type of explosive round is called a quarry closure shot. This is done by drilling a regular shot pattern only the shot holes are progressively shorter to further from the quarry wall that you get. What you are left with is a graded pattern of shot rock that leaves a slope down from the former quarry walls. This slope is often covered with topsoil and planted.
An underground mine is treated differently where in many cases a large concrete plug about 3 feet thick is placed over the shaft effectively limiting access to the mine. Some underground mines are capped using large metal grates that are usually used on deep level shafts that allows airflow to occur through the deep tunnels that helps prevent subsidence.
Older mines typically used wood beams, a foot or more thick, under loose rock or dirt as caps. Eventually the wood rots and sinkholes might develop. These mines are typically recapped with concrete, steel plates, expanding foam, or a combination.
Steel plates are used primarily on horizontal shafts, but are used on vertical shafts occasionally. Doors are added if access is needed. Holes are cut into the plate to allow for drainage as well as for a bat entrance.
Expanding foam is used mainly with vertical shafts where the use of the shaft is no longer needed. It forms a plug 6 feet or more thick. A 4-to-6-inch (100 to 150 mm) pipe through the plug allows for pressure equalization as well as drainage, or even as a bat entrance.
Closure planning has two different components. On-site planning is mostly about environmental rehabilitation and returning the landform to a reasonable condition. Off-mine closure is about loss of livelihood, which is a more complex issue.[5] An element of this is generating an offset against the high cost of environmental remediation issues, which in certain cases can exceed the value of the mineral that was mined originally. [6]

The Importance of a Business Plan in Gold Mining

A collection of classical capitals.


One of the most important document in gold mining or exploration, any mining or any business ventures is a good business plan that acts not only as a road map as to how the operations will proceed, but is also necessary to get capital for the operations of the business. Yes, gold mining in this sense is like any other business whether it is selling shoelaces or building rocket ships all business have to have a roadmap to their success.

If you are not familiar with a business plan it is a formal statement of the goals of your business. It also includes the reasons why you believe those goals are achievable and how you expect they can be achieved, and the way you are going to reach these goals. The business plan may also contain information about the personalities that will be conducting the operations necessary to achieve these goals.

A well-written business plan will also target whatever changes that may occur as to how the public perceives the business and its branding by the customer, client, taxpayer or the larger community as a whole. When your operations assume a major change such as the gold turning the copper at depth as often happens. It can be also used for planning new ventures or additional minds. Most principals or investors require a 3 to 5 year business plan since investors will look for their annual return of investment in that length of time.

There is a great deal of information about business plans on the Internet that can be found by Googling the phrase business plan. In addition there are also many, many templates that are available online where literally all you have to do is fill in the blanks and your business plan is written. Using one of these blanks is very helpful, however the best way to write an effective business plan is by scratch. At the very least by Googling business plan you can quickly gather a great deal of information as to how to write one.

No matter whether you use a pre-existing template or start writing your business plan from scratch you will quickly discover how much smoother everything goes for you. The business plan will not only direct you in operating the mine have but also make raising money far easier. There is not any operation on earth that does not benefit from a well written business plan.