Martelado (cob)

(en) Cobs, also called “Macuquinas” were crude silver coins issued in the Spanish colonies of the New World from about 1600 until 1820. The specificity of this technique relies in the planchets' preparation before hammering: rather than preparing a sheet of silver and cutting it into even round planchets, the bar of silver was just cut into pieces of the appropriate weight. This way, the size, shape and designs of the cobs was highly variable but they were the proper weight (if one was overweight, the moneyer just clipped another piece off). Those hastily produced coins were then sent to Spain or other countries, and also used for local transactions. Their rudimentary appearance encouraged clipping and counterfeits, further fueling suspicion toward this coinage.