(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 Sand, For Your Sand Filter. Filter sand, or silica sand, is specially graded to trap very small particles. This is the type of sand your filter needs in order to properly clean your above ground pool. It is usually sold in 50lb bags and can be found in any pool store.