Gravel Driveway Basics. Cost: $1 to $5 per square foot, though installation costs vary widely depending on where you live and the type of base required. Durability: Lifetime, with proper maintenance. Type of gravel: This depends on your area, but angular shapes are preferred over round.
Soil minerals form the basis of soil. They are produced from rocks (parent material) through the processes of weathering and natural erosion. Water, wind, temperature change, gravity, chemical interaction, living organisms and pressure differences all help break down parent material.
Soil is the top layer of the earth in which plants grow, a dark brown or black mixture usually of mineral and organic constituents, clay and rock particles. Soil is made of 45% minerals (sand,clay,silt), 25% Water, 25% Air and 5% Organics. Soil also includes dirt that is made of materials that plants avoid growing in.