PART  IV. Die Errors:

Vickers Test Mark left in die

See Planchet Errors HERE

Definition: A small pyramidal bump that appears in the coin’s field.  The pyramid marks where the tip of a Vickers Hardness Tester was pressed into the die face.  These test marks appear in coins from India, beginning in the 1930s and continuing at least through the last decade of the 20th century.  More than one test mark can appear on the same die face.

This 1982 India 50 paise coin shows a pyramidal Vickers test mark above the date and to the right of the Indian subcontinent.