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1800-102-2727The majority of elements are too volatile to remain on the earth by themselves. Instead, they occur as ores, which are complexes made up of different elements. Metals are made from ore, which is the raw material.
Minerals are solids that exist in nature and have specific chemical properties, colors, and toughness. Minerals include granite, basalt, and others.
An ore is a mineral through which a large volume of metal may be cheaply mined. Hence, all ores are minerals, but all minerals are not ores. Examples of ores include cinnabar (HgS), an ore of mercury, bauxite (Al2O3.2H2O), an ore of aluminum, among many others.
We see different types of ores in nature. Oxides, Carbonate Ores, Sulphide Ores, and Halides Ores are the four primary kinds of ores. A few examples of the same are given below:
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Minerals can be classified grossly into two categories: metallic and non-metallic.
Metallic minerals include gold, silver, copper, and other metals. Extraction of some of them needs understanding and skills, while others may be retrieved relatively quickly.
Carbon makes up the majority of non-metallic minerals. This group includes coal, oil, fossil fuels, and other similar resources.
Metallurgy is the technique of obtaining precious metals from their ores. On the grounds of their responsiveness, methods are designed to obtain metals from their ores. Electrolysis is utilized to remove very reactive metals from their ores, whereas reduction, roasting, and calcination techniques are used to remove metals with a moderate reactivity. Roasting and purifying are used to remove less reactive metals from their ores. The majority of less reactive metals are present in unbound forms, such as gold and silver.
There are principally three steps involved in the extraction of metals, and they are:
Ores are broken and ground initially, followed by the removal of matrices from the fine ore. This is referred to as ore concentration. The ore of very reactive metals, mildly reactive metals, and weakly reactive metals are purified first. This is a standard stage in the processing of all kinds of metal ores. Based on the ore's composition, it can be done in a variety of ways. It is usually done using one of four methods:
Physical concentration techniques include gravity separation, froth flotation, and electromagnetic separation, whereas chemical methods include leaching.
Then, depending on the responsiveness of the corresponding ore, metals are recovered using various specialized methods.
Highly reactive metals are those that are found at the top of the reactivity scale. Examples of these are sodium and potassium. Because these metals have a higher attraction towards oxygen than carbon, their ores cannot be converted to the oxide form, making the process more painstaking and costly. So instead, reduction by an electrolytic solution is used to extract these metals from their ores.
When sodium metal's ore, i.e., molten chloride, is electrolyzed, it yields sodium metal.
Moderately reactive metals, such as iron and lead, are found near the center of the reactivity table. Since removing certain metals from their oxides is easy, these are first converted into their oxides. Roasting and calcination are the two ways used to accomplish this.
Roasting converts ores to their oxides by heating rapidly in the existence of extra oxygen.
Calcination converts ores to their oxides by heating rapidly in the existence of a small quantity of oxygen.
These metals include mercury and copper. They are found near the bottom of the reactivity table. By simply warming these metals' oxides, they may be converted to metals.
For example, when HgS (Cinnabar) is subjected to high temperatures in the presence of oxygen, it changes to its oxide (HgO), which is converted to mercury when subjected to further heat at 300°C.
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