About in the Spring and Autumn Period (770 BC – 476 BC), the phenomenon of magnetite attracting iron was discovered in China. At that time, people likened this type of property to the love of mother to her children, which is also the very source of why magnetite is being called "Ci Shi" in Chinese because "Ci" means a loving mother here.
Heavy Media Gravity Separation Heavy media gravity separation involves using a mixture of fine media material, such as magnetite (SG 5.1) or ferrosilicon (SG 6.8), suspended in a slurry of water, to produce a media slurry with a specific gravity that will allow low density material(s) to float, and other high density material(s) to sink.
Formation of sand. Sand forms mostly by the chemical and/or physical breakdown of rocks. This process is collectively known as weathering. Physical and chemical weathering are usually treated separately, but in reality they usually go hand in hand and it is often difficult to separate one from another because they tend to support each other.
Feldspar — Feldspar is a rock-forming mineral. It is important industrially in making glass, ceramics, enamelware and soaps. It is also used in making bonding material for abrasive wheels, cements, fertilizer, tarred roofing materials and as a sizing or filler in textiles and paper.
Sand is a loose, fragmented, naturally-occurring material consisting of very small particles of decomposed rocks, corals, or shells. Sand is used to provide bulk, strength, and other properties to construction materials like asphalt and concrete.