(April 2015) Corruption in Brazil exists on all levels of society from the top echelons of political power (as seen in the MensalÃ£o Scandal and the Operation Car Wash and the Petrobras scandals) to the smallest municipalities.
Quartz sands, which are high in silica content, are used to make glass. When quartz sands are crushed they produce particles with sharp, angular edges that are sometimes used to make sandpaper for smoothing wood. Some quartz sand is found in the form of sandstone.
Silica is found in a wide variety of natural sources, including, most commonly, sand. Sodium carbonate, or soda, is used to lower the fusion point of silica, making glass light and workable. Soda is called a flux, because it brings the melting point of the mixture down.