Interesting denis, Chaos and Mark.
I had been led to believe that you needed a carbon edge to use the flint rods. Hence the reason people had started to using bits of hi carbon hacksaw blades. I thank all of you for correcting that.
Yes I have carried and used the magnesium blocks and have used them. With a hacksaw blade. That's a piece I can discard now. I don't like that you must construct a windproof enviroment so the magnesium shavings don't blow away, but I understand that they have saved lives.
I saw the matches with ferro rod on Ebay. It claims brand new and sealed. I have a bid on them now.