Copper(I) acetylide is a reddish solid. It is an explosive. It is a strange explosive because it does not release gas. When it detonates, it only releases copper and carbon. It can be formed inside copper pipes where acetylene flows through. It explodes because the acetylide is a reducing agent and the copper(I) is an oxidizing agent.
It is used in organic chemistry. It is a very sensitive explosive, too sensitive to be used.