Niewmismatic Error Coins

The Imitation Of Spanish Mexico 8 Reals Pillar Dollar (Ringgit Meriam) King Ferdinand VI (1747-1759) In Tin.
During the 1730's, the Cobs were gradually replaced by machine struck silver coins of 8 Reals value.The obverse featured the Coat of Arms of Spain. The reverse featured two crowned hemispheres or half worlds flanked by the Pillars of Hercules. Hence these Spanish silver 8 Reals came to be called "Pillar Dollars". In the Malay Peninsula, these coins were also known as "Ringgit Meriam" (Cannon Ringgit or Dollar). In the 19th Century, all these Pillar Dollars (8 Reals) came to be known as "Ringgit Tua"( Old Dollar) and were highly value by all.
The Spanish silver 8 Reals was the main coin in used in the Malay States of Kedah, Perlis, Kelantan and Patani where it was known as "Rial".

A lot of counterfeit Spanish silver 8 Reals Dollars were found in the market. Counterfeiters have been focusing their efforts on silver dollar sized coins for many years, producing fakes of Spanish Colonial 8 real coins. At first glance this fake looks like a typical corroded silver 8-real coin, dated 1757 and with the Mexico City Mint’s MM Mint mark.
Its details are not sharp. I have recognized it is a fake Pillar Dollar, when I felt its weight, it was significantly lighter (22.76gm). Next, I saw that its edge differs from common reales floral edges or the Laurel Leaf Design edge. 
This counterfeit "Ringgit Meriam" was inherited by me from Mr. DKWY, a very senior collector. He told me this counterfeit Spanish silver 8 Reals Dollar is probably made from alloyed of metals, which contained tin.This is the first time I came across a counterfeit Spanish silver 8 Reals Dollars that was made of tin.
Yesterday, when I got a opportunity to meet Master Tan Tai Seng and Mr. Tony Au, they confirmed to me the composition of this counterfeit "Ringgit Meriam" is tin.

Weight: 22.75gm.
Diameter: 39.00mm.
Thickness: 2.80mm.