Synthetic aggregate that includes a plurality of agglomerations. Each of the plurality of agglomerations may include a core; and a shell material disposed on the core. According to various embodiments, the construction aggregate may be non-flammable. According to various embodiments, at least one agglomeration of the plurality of agglomerations may have a plurality of cores. The core may include coal, a coal byproduct, and combinations thereof. According to various embodiments, the coal may be a type such as lignite, sub-bituminous, bituminous, and anthracite. The coal byproduct may be fly ash, bottom ash, shale coal, or coal gob.