Cullets
   |
 |
Clinker
Clinker is a general name given to waste from industrial processes particularly those that involve smelting metals or burning fossil fuels. Clinker often forms a loose, black deposit that can consist of coke, coal, slag, charcoal, grit and other waste materials. |
|
Pumice
Pumice is a highly vesicular pyroclastic igneous rock of intermediate to siliceous magmas including rhyolite, trachyte and phonolite. Pumice is usually light in colour ranging from white, yellowish, gray, gray brown, and a dull red. Pumice has an average porosity of 90%. |
