Experienced Help needed to fix a bent coin :)

YQQ

hopefully some of have some experience with trying to fix a bent coin.
the last collection I bought also contained a netherland 1 Cent 1830. However, it is bent.
Coin is worth about $100.
I have heard that bent coins can be straightened in some way with a hammer and two pieces of some kind of hard wood...
any suggestions? any experience ?
looking fwd to all your input.
thanks

lordmarcovan

I have used the "hammer and two pieces of wood" technique with reasonable success twice; once on a US silver 3¢ piece and again on a US half dime I found while detecting. Who knows why small silver coins like those (and yours) got bent so often. You'd think it would be the bigger ones, but I guess those were thicker.

(Edit- I thought you said Netherlands five-cents. So you have a slightly bigger coin than that, and copper? Might be even easier to straighten.)

Certainly the larger hammered coins of the medieval era got bent.

When I went detecting in England two years ago, I went with a club. They are so used to digging bent hammered silver pieces (which they call "tacoed" because the bent-double coin resembles a taco shell) that they have experts who specialize in straightening them. It is risky because a thin, tacoed coin that's been buried 700 years is brittle and can snap in two. They use heat annealing to soften the metal before straightening the coin.

I can try to find one of those experts if you want.

The 3¢ piece I straightened wasn't too badly bent, so three or four hammer blows with the coin sandwiched between the wooden boards did the trick.

The 1854 half dime I dug was tacoed to the point I thought it was a piece of an aluminum pulltab tongue when I found it. I did not use annealing but was able to mostly straighten it with the hammer and boards. It wasn't perfect, (and retained a crease) but was much improved. I guess I ran a risk of it breaking in two, but fortunately the metal hadn't crystallized that much so it was still flexible enough.

Sapyx

Mediaeval silver coins are often found bent because that is how they were often carried: folded around a piece of string worn around the neck. It was easier than trying to punch a serviceable hole in a thin coin and if you needed a coin to pay for something, you simply gave one of the coins a tug and it popped right off. Of course, if the string broke while you were riding or walking along and you didn't notice, you lost all your money; then a few centuries later, a metal detectorist finds a bunch of bent coins buried in the ground together - the string having decayed long ago.

Metal becomes more brittle as it ages - a process known as "crystallization". A bronze coin from 1830 should not yet have any noticeable crystallization effect. That being said, I personally wouldn't try to straighten a bent coin, unless it really was "bent like a taco" and I had trouble IDiing it properly while it's bent.

Muygrandeoso

I have used hard wood and a large bench vise...it worked pretty well