Fifteen boride composites were synthesized by hot pressing and evaluated by physical and incendivity testing as nonsparking tool materials. The incendivity tests, conducted by the Albany, (Oregon) Metallurgy Research Center of the Bureau of Mines, compared the boride composites with standard cobalt-bonded tungsten carbide material used for coal cutter bits. Two titanium diboride composites and two zirconium diboride composites out-performed cobalt-bonded tungsten carbide in wear resistance and reduced tendency to cause ignitions. However, three of these candidates exhibited undesirable chipping. The remaining candidates, a tib2- (ni,cu) composite, did not chip, nor did it cause ignitions at levels where cobalt-bonded tungsten carbide tools caused ignitions in the incendivity tests. The Bureau has for many years sought to improve safety in coal mining by developing methods for reducing the number and frequency of ignitions during cutting operations.