Abstract: A method of removing contaminants from the surface of an article is comprised of the steps of providing abrasive particles comprised of a material having the characteristic of reacting with oxygen to form predominately gaseous products of reaction and directing the abrasive particles in impingement onto the contaminated surface. The method is particularly applicable in removing contaminants from the internal components of air-breathing machines such as gas turbine engines. The abrasive particles may be entrained in an air stream flowing through the gas turbine engine whereby the particles are directed in impingement against the contaminated components. The abrasive particles may be comprised by carbon content of at least 70% by weight and a volatile content of less than 8% by weight and may also have an erosivity within the range of 0.004 grams to 0.15 grams.