Afghan 5 Rupees; Defective Planchet Or Fake?

Interesting coin. Looks like there could be a retained (struck through) fin or piece of scrap metal on the edge of the coin to the left and slightly below the toughra.

The planchet could, I guess, be wavy (thicker at some points than others). But in recent times that type error happens less than it did a century ago.

I would look in the direction of a Grease Filled Die. Die grease is actually a mix of industrial waste in an oily or greasy base. It can be VERY hard and if it fills the recesses in the die the portion of the image that was filled simply does not appear.

Some people call coins like this "weakly struck" but some portions of the coin seem far better struck than others so a low pressure strike (which is uniform in pressure over the entire die face) is ruled out.

I have no idea of the metal used to make the originals or the physical parameters of this coin, but it looks like a typical modern strike and if the coin is the correct dimensions, I would believe it is real.

If this was the first use of a modern press - poor maintenance is the most likely culprit. If they over apply grease to an older worn press - this result is exactly what would be expected. A dusty environment can also result in a similar buildup of gunk.

A strike through is always interesting. They are one of my favorite mint production errors.