Brian May's plectrum

I was wondering if anyone could tell me which Australian coin is closest to the coin that May used as his plectrum - i'm trying to get his sound.
I am assuming it is the 5 or 10cent piece or are none similar enough.

Cheers

He doesn't use Australian coins because of the zinc content. He is allergic.

try getting hold of an old english silver sixpence off ebay

Brian uses the old six-pence pieces, from before Britain decimalized in 1972.

I have a few of these, but I've actually found an Austrian coin with an even more serrated edge, making the tone that much sweeter and clear.

I've mucked around with the 5 cent piece. It's interesting, but not enough for me to want to change my habits.

The best sound I've gotten so far was with a ten million mark note from the Weimar Republic. Bit of a handful.

Try a greek Euro coin. They're gonna be as rare as a six-pence. ;)