Metal and Non-Metal

Minerals

A mineral is a naturally occurring, inorganic solid with a defined chemical composition and a specific crystal structure. It is extracted from mine and has great economic value. For example: Quartz, Gems, Hematite, etc.

Ore

An ore is a mineral that contains a sufficient amount of metal. When we extract metal from the ore, it can be done in significant quantities, resulting in profit. It’s important to note that while all ores are minerals, not all minerals are ores because not every mineral contains metal.

Ores of Iron, Aluminum, Copper, Silver, and Gold

Metallurgy

Metallurgy is the branch of science that studies the physical and chemical properties of metallic compounds, and the extraction of pure metals from their ores.

General Steps of Metallurgy

1. Mining

In the very first step, the metal ore is collected from the mine. The process of collecting metal ore from the mine is called mining.

2. Grinding

Then, the ore is grinded in the factory into smaller pieces. The process of grinding big metal ore into small pieces with the help of a machine is called grinding.

3. Concentration

The grinded ore contains metals as well as impure substances like sand, stone, soil etc. So, the process of removing impure substances from the ore is called concentration. Different methods are considered depending on the nature of metal and impure substances. Some of them are:

Gravity Separation: if the constituents have different densities.

Magnetic Separation: if the constituents are magnetic and nonmagnetic.

Froth Floatation: if the constituents are hydrophilic and hydrophobic.

4. Oxidation

Then the ore is forwarded to the oxidation process. The process of converting metal into its oxide i.e. metal oxide is called oxidation. Oxidation is done because it is very easy to extract pure metal from metal oxide. There are two methods for oxidation.

Roasting: The process of heating the ore in the presence of sufficient oxygen is called roasting. Roasting is done to those ores that do not have oxygen in it. For example, Zinc Sulfide(ZnS) into Zinc Oxide(ZnO).

Calcination: The process of heating the ore in the absence of oxygen is called calcination. In calcination the metal carbonate is converted into metal oxide. For example, Calcium Carbonate (CaCO₃) into Calcium Oxide(CaO).

5. Reduction

Then, the metal oxide is forwarded in the Reduction process. The process of removing oxygen from the metal oxide is called reduction. In most cases, we use reducing agents like carbon, carbon monoxide, hydrogen etc. for the reduction. 

Smelting: The process of reduction in which the metal oxide is heated just above the melting point of metal in the presence of reducing agents is called smelting. In this method, the metal is extracted in a molten state.

6. Refining

The metal received after the reduction process; it still contains a tiny amount of impurities(a very small percentage). So, the process of extracting metal in very pure form is called refining. There are two common methods of refining.

Distillation: In this method, we boil the metal to remove impurities.

Electro-Refining: Here, we use electrolysis to get rid of impurities.