2016-10-14 Fri

This 2014 2-rupee error coin was struck using a reverse die which was rotated 65 degrees counter-clockwise with respect to the obverse die and also tilted up at one pole. This resulted in a coin with the area near the statue’s base unstruck.

Die alignment errors could occur with respect to all three axes and planes which means that they can rotate, tilt, pivot, or slide. Significant die tilt occurs majorly due to the loose hammer die operating during an unstable situation. The anvil die will generally be not tilted as it is held by the surrounding collar. The power and magnification of the tilt would vary from one strike to the next. If there is a pattern found in the direction and impact of the die tilt then it is probably caused due to a tilted die assembly.

When a die spins in its recess it leads to die-rotation errors which are not because the entire die assembly is rotating. In such cases, it is mostly the hammer die which rotates probably because the hammer die isn’t mounted as securely as the anvil die.

When a spinning hammer die sits inside a tilted die assembly, both tilt and spin would independently occur. 9 2014 India 2-rupee coins were struck by the same die pair. This particular error is caused due to a rotating and tilted hammer die as a huge die crack is seen on the reverse. All of the coins are struck out-of-collar and do not have evidence of collar contact. In this series, both the obverse die or the reverse die can be used as the hammer die but the former case is common.

All coins, except one of them, features a rotated die error with a significant change in the extent of rotation. The die tilt observed is less as compared to the rotation which can be observed based on the weakly struck areas on the obverse. This suggests that the obverse die was fixed, while the spinning reverse die was loosely held by a tilted hammer die assembly. The degree of die tilt and the striking pressure varies slightly leading to faintly visible to completely absent designs.