128. malaysia 1 sen 1986 damaged planchet

image 1: obverse and reverse of the coin

    Pretty damaged coin. It seems that this coin is infected with some coin disease.

81. Malaysia Included Gas Bubble Planchet 1 sen 1996

image 1: obverse and reverse of the coin

    Another error coin!

    This error is under the category of damaged and defective planchets. According to numismaster.com, they are two types of bubble-related planchet error, Bubled Plating Planchet and Included Gas Bubble Planchet. Still not sure which one is precisely described this coin.

     In my opinion, this type of error, the bubble which can be seen on the obverse of the coin is caused by improper planchets making during its manufacturing process. When the striking occurs onto the planchet, probably the temperature of the planchet is increased, hence making the gas entrapped inside the planchet exploded. The high increase in pressure and temperature during the striking process or just right after the striking process, damaged the planchet, which act as a vessel for the gas. Just a wild hypothesis though.

    By the way, am I right?