People are engaged in gold mining since ancient times. During the Neolithic era of ancient people began to attract this precious metal which was often found the whole nuggets. And how extract now gold when there is practically no gold nugget left on Earth already?
Instruction
1. Gold is a soft yellow metal. This metal is rather heavy and at the same time kovka. So, for example, from 1 gram of gold it is possible to extend the thinnest wire which will last even on 3 kilometers, or to make the foil smaller on thickness, than a human hair by 500 times. But we will deal with the main issue of this article.
2. In the earth gold content in pure form very low. Scientists found out such fact that if to scatter gold evenly in earth crust, then from ton of the earth it would be possible to allocate only 2 g of gold. In gold water it is a little too.
3. Extract gold differently. But all ways of gold mining (both industrial, and nonindustrial) are based on its physical and chemical properties.
4. Washing – the most widespread way. Based on the high density of metal. While other metals and sand wash off, gold accumulates directly in a tray. Washing of gold is very long and tiresome process therefore it is widely used at the heart of the in developing countries. On the other hand, this way appeared the first. It does not demand any financial investments.
5. Amalgamation. This way of production is based on ability of mercury to enter easily connections with gold. Gold-bearing ore is crushed for this purpose, then there add mercury. Amalgam (mercury mix with heavy metals) turns out. Further this mix is processed in the special way, taking compounds of mercury with gold and dividing them. A good way, but it assumes availability of expensive reagents and the equipment. Besides, vapors of mercury are poisonous.
6. Cyanation is based on ability of the most hydrocianic acid and its salts to dissolve gold in itself. Let's not go deep into chemistry because this way definitely does not "threaten" ordinary loner gold diggers. It is only possible to add that still the "royal vodka" representing mix of the concentrated sulfuric and nitric acids can dissolve gold.
7. There are some more ways, such as regeneration and others, but these ways assume generally expensive experiments with chemicals. Here also it turns out that we can extract gold only in the antiquated way: sitting on a stone with a tray in hands and washing gold on particles.