Kelim, Chapter Twelve, Mishnah Seven
Today’s mishnah deals with the susceptibility to impurity of invalidated coins that have put to a secondary purpose.
1) If a dinar had been invalidated and then was adapted for hanging around a young girl’s neck it is susceptible to impurity.
2) So, too, if a sela had been invalidated was adapted for use as a weight, it is susceptible to impurity.
3) How much may it depreciate while one is still permitted to keep it?
a) As much as two denars.
b) Less and he must be cut it up.
Section one: A coin is not susceptible to impurity, but if it is invalidated and cannot be used and is then hung around a young girl’s neck as jewelry, it is susceptible.
Section two: A sela is a heavier, more valuable coin, worth four denars. If a sela was invalidated, but then used as a weight, it is susceptible to impurity.
Section three: It is forbidden for a person to hold on to an invalidated coin, lest he deceive people with it and exchange it for a real coin. However, if the coin is obviously defective, he can keep it because people will know that it is defective. Our mishnah therefore asks how much the coin can depreciate before he has to cut it up and get rid of it.
The answer is that it can be up to two denars defective. Two denars is equivalent to a shekel. If it has depreciated more than this, he may not hold on to it, lest he try to exchange it for a shekel.