Sand
Sand, mineral, rock, or soil particles that range in diameter from 0.02 to 2 mm (0.0008-0.08 inch). Most of the rock-forming minerals that occur on the Earth's surface are found in sand, but only a limited number are common in this form. Although in some localities feldspar, calcareous material, iron ores, and volcanic glass are dominant constituents of sand, quartz is by far the commonest, for several reasons: it is abundant in rocks, is comparatively hard, has practically no cleavage so that it is not readily worn down, is nearly insoluble in water, and does not decompose. Most quartzose sands contain a small quantity of feldspar, as well as small plates of white mica, which, though soft, decompose slowly.
Bauxite
Bauxite ore is the world's primary source of aluminum. The ore must first be chemically processed to produce alumina (aluminum oxide). Alumina is then smelted using an electrolysis process to produce pure aluminum metal. Bauxite is typically found in topsoil located in various tropical and subtropical regions. The ore is acquired through environmentally responsible strip-mining operations. Bauxite reserves are most plentiful in Africa, Oceania and South America. Reserves are projected to last for centuries.
Manganese
Manganese is a chemical element with the symbol Mn and atomic number 25. It is a hard brittle silvery metal, often found in minerals in combination with iron. ... Manganese is also an essential human dietary element, important in macronutrient metabolism, bone formation, and free radical defense systems.
Iron Ore
Iron ores are rocks and minerals from which metallic iron can be extracted. There are four main types of iron ore deposit: massive hematite, which is the most commonly mined, magnetite, titanomagnetite, and pisolitic ironstone. These ores vary in colour from dark grey, bright yellow, or deep purple to rusty red. Iron is responsible for the red colour in many of our rocks and the deep red sands of the Australian deserts, and is a key ingredient in steelmaking.
