Bitten Edge 2c

how do I post a pic?

You can also go to photobucket, upload pictures to that after making an account, then copy the little link down below the picture, the link that says Image Link.

http://www.photobucket.com

A "bitten edge" is what the Americans call a "clipped planchet".

A genuine "bitten edge" is caused by an error in the planchet cutting process. A "curved bite" is caused by the planchet-cutting punch ( a machine like a giant cookie-cutter, only with metal rather than dough) accidentally punching too close, taking a "bite" out of the next coin. A "straight bite" is caused by the punch getting too close to the edge of the rolled sheet of metal, and clipping a piece right off the edge of the roll. A simple demonstration:


Note that the "biting" is taking place before the coin is struck, even before it was rimmed prior to striking. This creates an important characteristic feature of a genuine bitten edge, known as the "Blakesley Effect". This is where the rim and design of the coin directly opposite the "bite" is very weakly struck. This is caused by the rimming machine not being able to squeeze the coin properly where the bite has taken away some of the metal, leaving a gap in the rimming directly opposite the bite.

"Bitten edge" errors are commonly counterfeited - anyone with a workshop metal punch or boltcutters can do a passable imitation - but such fake errors will often lack the distinguishing characteristics of a real clipped planchet, like the Blakesley Effect.

This website probably explains it better than I do.

I wouldn't call it "bitten". I'd call it "broken", or a planchet flaw - a gas bubble or defect was present in the metal, causing a jagged piece to break off. The piece may have broken off before, during or after the actual striking; it's hard to tell, but I suspect not before strike; I think the striking would have obscured the defect a lot more than that.

My hypothesis would be a defect in the alloying of the metal, making it more brittle in that spot; the nearby "carbon spot" on the reverse is probably another piece of poorly mixed alloy causing spot corrosion.

Learjet's avatar seems to be much the same kind of error, only more spectacular.

If it weren't for the provenance, I'd have assumed it was post-mint damage of some kind.

Bitten edge coins are collected in Australia. They're more sought out in Pre Decimals, but collectors who come across a decimal one would most likely keep it. I know I would. As for value, maybe between $1 & $5.

There's 5 x 2¢ on ebay at present, all from the same seller. Do a search in coins for 'bitten'.