PURPOSE: To produce ceramic particles by forming a suspension of clay in water, adding ash and organic matter to the suspension, reducing the water content of the suspension to less than a particular amount to form a sludge, forming particles of desired size and shape, and firing them.

CONSTITUTION: A suspension of clay in water is formed, ash and organic matter are added to the suspension, and the water content of the suspension is reduced to less than about 60 wt.% to form a sludge. Particles of desired size and shape are formed and the particles are fired at a temperature and for a time sufficient to form ceramic particles, thereby producing the ceramic particles. The ceramic particles produced are light-weight aggregate which has found considerable utility (in concrete products, for example). The ceramic particles are environmentally benign and have very high compressive strength. They also have utility in other fields (e.g. as insulation, landscaping material, etc.). Ash and waste paper are treated to convert them to useful products and to reduce environmental pollution posed by such ash and waste paper.