The early days of prospecting for gold in this era were certainly full of adventure and action. Take a look at the nearby cache “Lucky Mr. Richie” (GC69VJR) for an insight into this particular site.
It is assumed that the sinking of a Government bore hole would have exposed the gold deposits, but the purpose of this Earth Cache is to gain an understanding of the nature of Gold discovery on a broader scale.
There are certain unique aspects of the heavy metal that go toward an understanding of it.
The first aspect is that Gold cannot be created. With all the resources available to modern man, and with the understanding we have of the natural world, it is claimed that Gold cannot be manufactured. Whilst this is true in real terms, it is not really a fact. Gold can be manufactured.
Theoretically, using super-charged electrons in the Large Hadron Collider at CERN, Switzerland, it is possible to simulate the creation of gold from a Nobel gas one atom at a time. The theory goes something like this: a single atom of Hydrogen under extreme force of unattached electrons creates Helium, and so forth, increasing in the neutron count of the element until the 197th cycle of this process, and an atom of Gold is created. Continuing to create atoms of gold in this manner, eventually a gram of gold is brought into existence.
It is believed that the collapse of a Black Hole and early birth of a star – The Big Bang, are what started the formation of matter in the Universe. As solid mass was created, one of the component elements was Gold.
For this process to be recreated within a controlled environment, like at the CERN laboratory, the time required would be slightly over 4 Billion years, almost as old as the very Earth itself. So in reality we cannot create or manufacture Gold, and all the gold available is fixed and unchanged.
http://www.astrosurf.com/joseribeiro/Textos/The%20Story%20of%20Gold.htm
Please be aware that this site is not a recognised Geocaching site, and the Owner nor Groundspeak can be accountable for the consequences of visiting such a site. Ensure you practice safe surfing. It is your own responsibility.
Aurum, the Latin name for Gold, is a heavy metal. The elements that came into being when the earth was formed, known as Primordial Nucleosynthesis, contained huge amounts of heat. At this time, all matter was liquid, and was in a combined solution. Gravity marshaled the liquid into a concentrated mass, and as the outer edges of the liquid orb were exposed to the coldness of space, they solidified and a crust was created. This crust or mantle was the birth of the solid we call Earth.
As the Magma, or thick unguent, cooled down and hardened, the nature of the elements changed in becoming solid. Each element behaved according to its atomic property as it solidified. It should come as no surprise that the Earth mantle thus contains Gold, amongst other metals.
The second aspect of this insight into gold is where it is found. The progression of gold in solution from within the core to a solid deposit beyond the mantle and closer to the surface of Earth, is directly dependent upon geological action.
The deposit of gold involving the change of state from liquid to solid is known as a Lode deposit, and there are three theories as to how a Lode Deposit would come to be.
1] A popular and now slightly dated hypothesis holds that the Lode deposit is a consequence of the ground water geothermal cycle. As rain water is collected upon the surface of the earth, it permeates down through fissures and joints, drawn by gravity toward the core. As it approaches the core, it warms up, and lateral movement occurs when there is an intrusion in close proximity. As the water heats up, it begins to rise, carrying with it in suspension particles of gold and other elements. In rising through the cooler sedimentary rock, the water cools down and the precipitated metals are lodged in the passage to form veins or blanket like ore bodies.
2] Another hypothesis is that gold bearing solutions may be expelled from the magma as it cools down, creating deposits as the metal ore precipitates from the magma. The finding of lode deposits near granite and basalt intrusions lends support to this theory.
3] A third hypothesis is applied mainly to gold-bearing veins in metamorphic rocks that occur in mountain belts at continental margins. In the mountain-building process, sedimentary and volcanic rocks may be deeply buried or thrust under the edge of the continent, where they are subjected to high temperatures and pressures resulting in chemical reactions that change the rocks to new mineral assemblages (metamorphism). This hypothesis suggests that water is expelled from the rocks and migrates upwards, precipitating ore materials as pressures and temperatures decrease. The ore metals are thought to originate from the rocks undergoing active metamorphism.
A secondary deposit process is also at work. This is known as Placer Deposits, and is whereby the Lode deposit is eroded, disintegrated or is reduced by nature. Placer deposits form when the Lode rock undergoes a change (metamorphic rock) and the gold is moved by gravity to a new placing. Usually this process involves water in conjunction with gravity, and is a consequence of the pliable nature of gold. Under extended weathering, gold is not affected, but retains it's quantity. Pieces of gold are drawn / pushed/ roll into the lowest point from the lode deposit, and such is then carried mechanically by the running water. When the water enters an eddy, or runs into a slower flowing pool of water, the gold will stop being propelled into a direction and a Placed deposit begins. This is by far the more lucrative deposit to commerce, and is the more romantic deposit to an outsider.
There is a third aspect to finding gold that needs to be introduced.
This theory holds that gold is a product of the creation of matter in space. It goes on to posit that not only Earth contains gold, but every solid that has been created would also contain gold. It thus follows that when debris from space collide with Earth, in the form of meteorites, each collision would bring with it an appropriate injection of gold. This additional gold would not be in solution deep within the core, but would be embedded within the sedimentary surface of the planet. A fine example lending support to this aspect is the goldfields of Witwatersrand. There is sufficient evidence to suggest that the Witwatersrand area was a consequence of the Vredefort Impact. Verifiable evidence points to a huge meteorite colliding with earth with its epicenter being near Vredefort, in the Free State. There was a period, early in the life of the earth (some 3.5 to 4 Billion years ago) when the Earth was subject to an enormous bombardment of space matter. Known as the Late Bombardment Period, it is held that this injection of Gold into the planet has accounted for the gold that is found without the inner mantle.
But for however the gold was deposited, and whatever forces were at work in determining where the gold mine should be, this site remains a testimony to the desire of man to go to extreme depths to collect this valuable mineral.
References:
South African Geology.
Schwarz, Ernest H.L., 1912
United States Geological Society : Fact sheet: Gold
Authors - Harold Kirkemo, William L. Newman, and Roger P. Ashley
The Story of Gold
Ribeiro, Jose., Het611A Semester 1, 2002
Gold Mineralization in Natal, South Africa - Thesis
W.D. Bullen, R.J. Thomas and A. McKenzie , 1994
http://en.wikipedia.org/wiki/isotypes_of_gold
In order to retain your FOUND Status, you must respond to the following
tasks. Please submit your response to the CO by way of message
from within the App.
Every FOUND IT entry must have a corresponding approved submission,
The evaluating of the response is at the sole discretion of the Cache Owner.
TASKS TO BE UNDERTAKEN
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Describe 3 methods that a Gold deposit could form, in your own words.
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Have a look at the surrounding country side on your way to the GZ. Observe the topography of the area, both at the GZ and in the entire visible area around you. Notice any evidences of mountains or canyons. Is there any sign of tectonic activity around you? With this in mind, what do you think would have caused this deposit of gold? Explain why you think this.
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(Site Verification) There is a wooden shed adjacent to the entrance to the mine. What function does this serve now?
OPPTIONAL ACTIVITY
Task 4.
To appreciate the effort that was undertaken to work this mine, you might want to carry out this task.
Using both hands, scoop up as much soil from the bank or from the water edge. Then place your hands with the soil into the water and gently shake them, allowing the smaller grains of soil to slip off. Continue doing this until you have only the larger stones left in your hands. You are actually simulating the Gold Panning Process – the method that was used on the mine back when it was active.
Now determine the volume of soil held in your hand ( length of one palm X length of other palm X 22; answer divided by 7 . Now multiply that by the height of the soil you collected. Formula is ~ volume = π r²h ~)
Divide 15,000 by your answer, and that would tell you how many times the top layer of soil had to be panned, simply to open the mine 20 cm deep!
You may want to include this number in your Found It log!
You may wish to log a picture of yourself at the GZ if you want. (Optional)
Please remember to send responses within a 7 day period after logging this Earth Cache.