Abstract: An interlocking block has a specially configured interlocking block element having accurately positioned surfaces which are inclined to provide a guiding and seating action and an accurate position stop for an adjacent block that is interengaged with the interlocking block element.

Abstract: The invention is an improved building material for constructing buildings, a building material which also has insulating qualities. The building material may be formulated as a mortar or as a concrete like composition. The materials consist of cement, regular fine aggregate, regular coarse aggregate, volcanic ash in coarse aggregate form, perlite in fine aggregate form, and water. The materials can be compounded in numerous formulations, a preferred formulation is provided. The prepared materials can be plastered or used as a binder in one case, and molded, paired in forms, or otherwise shaped in the other case.