Product Code Database
Prospecting is the first stage of the geological analysis (followed by exploration) of a territory. It is the search for , , precious metals, or mineral specimens. It is also known as fossicking.
Traditionally prospecting relied on direct observation of mineralization in rock outcrops or in sediments. Modern prospecting also includes the use of geologic, Geophysics, and Geochemistry tools to search for anomalies which can narrow the search area. Once an anomaly has been identified and interpreted to be a potential prospect direct observation can then be focused on this area.
In some areas a prospector must also stake a claim, meaning they must erect posts with the appropriate placards on all four corners of a desired land they wish to prospect and register this claim before they may take samples. In other areas publicly held lands are open to prospecting without staking a mining claim.
Once a small occurrence or show was found, it was then necessary to intensively work the area with pick and shovel, and often via the addition of some simple machinery such as a sluice box, races and winnows, to work the loose soil and rock looking for the appropriate materials (in this case, gold). For most base metal shows, the rock would have been mined by hand and crushed on site, the ore separated from the gangue by hand.
These shows were commonly short-lived, exhausted and abandoned quite soon, requiring the prospector to move onwards to the next and hopefully bigger and better show. Occasionally, the prospector would strike it rich and be joined by other prospectors to develop a larger-scale mining operation. Although these are thought of as "old" prospecting methods, these techniques are still used today, but usually coupled with more advanced techniques such as geophysical magnetic or gravity surveys.
In most countries in the 19th and early 20th century, it was very unlikely that a prospector would retire rich even if he was the one who found the greatest of lodes. For instance Paddy Hannan, who discovered the Golden Mile, Kalgoorlie, died without receiving anywhere near a fraction of the value of the gold contained in the lodes. The same story repeated at Bendigo, Ballarat, Klondike and California.
Other gold rushes occurred in Papua New Guinea, Australia at least four times, Fiji,Fiji through a Prism of Geology and Mines Inspection. Chapter 5 in: White F. Miner with a Heart of Gold: biography of a mineral science and engineering educator. Friesen Press, Victoria. 2020. ISBN 978-1-5255-7765-9 (Hardcover) 978-1-5255-7766-6 (Paperback) 978-1-5255-7767-3 (eBook) South Africa and South America. In all cases, the gold rush was sparked by idle prospecting for gold and minerals which, when the prospector was successful, generated 'gold fever' and saw a wave of prospectors comb the countryside.
Knowledge of previous prospecting in an area helps in determining location of new prospective areas. Prospecting includes geological mapping, rock assay analysis, and sometimes the intuition of the prospector.
Prospecting of minerals found in mobile fluids, as is often the case of lithium, adds a "temporal element" to be considered.Cabello, J. (2022). Reserves, resources and lithium exploration in the salt flats of northern Chile. Andean Geology. 49 (2): 297–306. doi: 10.5027/andgeoV49n2-3444. Retrieved July 2, 2022.
Magnetic separators may be useful in separating the magnetic fraction of a heavy mineral sand from the nonmagnetic fraction, which may assist in the panning or sieving of gold from the soil or stream.
Another relatively new prospecting technique is using low frequency electromagnetic (EM) waves for 'sounding' into the Earth's crust. These low frequency waves will respond differently based on the material they pass through, allowing for analysts to create three-dimensional images of potential ore bodies or volcanic intrusions. This technique is used for a variety of prospecting, but can mainly be for finding conductive materials. So far these low frequency EM techniques have been proven for geothermal exploration as well as for coal bed methane analysis.
|
|
