How To Straighten Silver Hammered Coin - Tutorial, page 1
Simple Method for Unbending Bent Coins Without Special Tools & Annealing
As thin-sectioned hammered and milled silver coins are more susceptible to bending than regular coins of later times, it is not unusual to dig up a medieval silver coin with a slight curvature. In plowed fields, a few of such coins get badly bent and, in worst cases - clipped, by a plough. But once in a while there is an unusual case when fragments of a dug hammered silver coin are crumpled or folded by a human!
Shown on a picture to the right is this rare case - two pieces of the 10th century Kufic (also Cufic - angular form of the Arabic alphabet) coin's half are folded into one piece. The reason someone did that 10 centuries ago was simple - to preserve the denomination's integrity.
Most likely, this coin was cut in two halves by a merchant to give a customer a monetary change during a transaction at the local market. Whatever happened to this half, the person put it together after an accidental breakage to keep its silver weight intact. Back in those times, prices for goods were expressed mostly in silver weight as many silver coins of different kingdoms and regions were circulating in Europe. This Persian Dirhem with Arabic inscriptions from the Koran on it had traveled all the way to the Baltic seashore.
Now I decided to attempt to straighten this coin. I did not use annealing technique (described in my article - "How To Straighten A Bent Silver Coin Using Annealing") because the coin's numismatic value had already been destroyed: the coin was cut, the half was fragmented, and a bend spot was badly cracked under maximum pressure applied by the medieval person durring bending. Also the large fragment's tip - the smallest piece, was missing anyway. Actually my main purpose of unbending this specie was to be able to ID it correctly.
The following pictures depict just a simplest way of unbending the crumpled coin, and this should be normally done between annealing sessions.
To straighten the coin I used two thin plastic sheet plates (similar pieces can be cut out of a rectangular Philadelphia Cream Cheese container, or an old credit/debit card), two regular plastic knives and a block of smoothed wood. You can use a set of small Bent Nose Pliers with jaws coated in rubber or chamois leather sleeves, or any non-metal tool to be used for actual straightening of the coin. Do not use bare metal tools for straightening the coin not to damage its surface and reduce its value. Use something softer than metal to cover working surfaces.
• First, I inserted one plastic plate inside the fold.
• Then I squeezed another plate inside the fold so that both plastic plates could be used as protection for the coin metal against accidental scratches of a plastic knife.
• The straight back of the knife's blade is hard which is useful for this task but can be harmful if not used carefully.