Minerals

Mica

Step 1: Minerals are classified into two types — metallic and non-metallic. Step 2: Metallic minerals contain metals in their composition. Copper, Gold, and Manganese are all metallic minerals because they contain metals. Step 3: Non-metallic minerals do not contain extractable metals. They are usually dull, light, and brittle. Step 4: Mica is a non-metallic mineral found in sedimentary rocks. It is brittle and used as an electrical insulator. Step 5: Therefore, Mica is the correct answer as it is a non-metallic mineral.

South Africa

Step 1: Manganese is an important metallic mineral used mainly in making iron and steel. Step 2: India ranks third in the world in manganese production. Step 3: Other countries that produce manganese include China, Australia, Brazil, and Malaysia. Step 4: However, the largest producer of manganese in the world is South Africa. Step 5: USA and Germany are not among the leading producers of manganese. So South Africa is the correct answer.

Nuclear defence systems and nuclear generation of electricity

Step 1: Uranium is a radioactive metallic mineral, which means it releases energy from its atoms. Step 2: Because of its radioactive nature, uranium is used in nuclear defence systems (weapons and military). Step 3: It is also used in nuclear power plants to generate electricity — this is called nuclear energy. Step 4: It is additionally used in nuclear medicine, X-ray machines, and electronic instruments. Step 5: Making jewellery and coins is the use of gold, electrical wires use copper, and cement uses limestone — none of these are uses of uranium.

Open pit mining

Step 1: Mining is the extraction of valuable minerals from the Earth. It is broadly divided into surface mining and underground (subsurface) mining. Step 2: Surface mining extracts minerals that are near the surface of the Earth. Step 3: The three common types of surface mining are — Open pit mining, Strip mining, and Quarrying. Step 4: Open pit mining involves digging large holes or pits in the ground to extract ores and rocks near the surface. Step 5: Shaft mining and underground tunnelling are types of subsurface/underground mining. Drilling is used to access oil and natural gas. So Open pi