A good buddy of mine , who is a heavy equipment operator , told me about this stuff when I was asking about flint . Anyway he got me some and I ,crudly, chipped away at it until I had a piece about the same size as the flint in my Firestorm.I put it in the hammer of my gun and man it gives off some really good spark.Don't know how long it will last , but it is free and very easy to come by. has anyone else used this stuff? will this damage my frizzen? thanks.