Fly ash
Fly ash brick (FAB) is a building material, specifically masonry units, containing fly ash and water. Compressed at and cured for in a steam bath, then toughened with an air entrainment agent, the bricks can last for more than cycles. Owing to the high concentration of calcium oxide in fly ash, the brick is described as "self-cementing". The manufacturing method saves energy, reduces mercury pollution in the environment, and often costs 20% less than traditional clay brick manufacturing.