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One sunny day,ancient people who came to the riverbank to catch fish with iron clubs in hand discovered a"mysterious thing " shimmering on the river bed. This is probably how human beings encountered gold for the first time. Gold dust is weathered gold ore that accumulates with sand on river beds and other locations. It is a gift from the awesome power of nature.
 In Japan,prospectors who made a living by finding metal deposits such as gold,silver,and copper were called yamashi ("mountain masters ").They needed many years ' experience,[sharp ] instinct,,and the perseverance to walk the mountains day in day out —and a great deal of luck. Nevertheless,there were some ground rules for locating gold deposits,some of which are still applied today.
First,you observe the mountain. You look at it from the south on a clear summer day,just after a rainfall. You must be within 2 kilometers of the mountain. If you spot irregularities in the mist near the summit,you should observe the mountain from the same viewpoint on a clear, moonless night. If the summit appears to glow,there is a good chance of finding deposits. It is said that experienced prospectors were able to identify the type of mineral from the glow.
The phenomenon is believed to be caused by the energy emitted by metal,which makes sense if the deposits are exposed at the ground 's surface. There have been cases where deposits were discovered by certain forms of light in Britain and the Americas,as well as in Japan.
Another effective method is to follow upstream a river where gold dust is found. Follow the river through valleys to the foot of a mountain. Walk patiently, meticulously examining stones on the riverbank and rocks exposed on cliffs. This is a more rational method of exploration.
Today,methods employed are obviously more scientific. The most common method of exploration uses exploration satellites for very large areas,and remote sensing using aircraft and helicopters for wide areas. These measure magnetic fields to detect anomalies. Physical exploration methods provide a general picture of geological conditions by measuring electricity and gravity,and geochemical exploration analyzes surface soil such as earth and sand,narrowing down the location of potential deposits.
Once the target is pinpointed,drilling commences to study precise geological structure. The depth of the hole is usually 500 –1,000 meters. The core brought to the surface is carefully observed by experts,and samples are finely ground and analyzed. Once the existence of the deposit is confirmed,the question of whether it can be profitably mined must be considered.
The above exploration method has continued in Japan since the Ministry of International Trade and Industry established the Metal Mining Agency of Japan in 1960.A partnership between companies,universities,and other research organizations conducts deposit surveys in promising areas in Japan.
The Japanese exploration system has a solid reputation worldwide. Japan constantly receives requests from the Philippines,Turkey,China,and Latin American countries for technical cooperation in wide-area and precision surveys. A growing number of Japanese engineers and researchers are working in this field overseas. |
