They don't seem to be. Flints are made up of various products than ferro rods, they’re tougher to strike, and they don’t create as warm of a spark. In the case of a ferro rod, the material that may be getting shaved off the rod produces the spark, as a http://edgarsiyma.bloguetechno.com/5-Easy-Facts-About-ferro-rods-Described-38068314