Introduction

Alloys: These are those metals which are mixed with iron as base.

• Biogas: Energy produced by using shrubs, form waste, animal and human wastes.
• Conventional Sources of Energy: Traditional sources of energy like coal, petroleum, natural gas.
• Minerals: Naturally occurring substances on the earth’s surfaces having a definite chemical composition.
• Non-conventional sources of energy: Renewable sources of energy which are recently developed like solar, wind tidal, etc.
• Open cast mining: A method of mining by removing the overlying materials to extract the minerals from shallow depth.
• Mining: An economic activity which deals with profitable extraction of minerals.
• Placer deposits: Minerals which occur as alluvial deposits brought down by the rivers such as gold, silver, tin, etc.
• Rocks: Natural substances which consists of one or more minerals.
• Shaft mining: A method of mining where vertical and horizontal shafts are made to extract the minerals from deep under the earth.