HALF REAL ? (Silver Alloy) SS11Obverse: In Arabic "Al Sultan Al Kedah" (The Sultan of Kedah)
Reverse: In Arabic "Muhammad Shah"
Edge: Plain
Weight: 1.9 g
Diameter: 15 mm
Composition: Silver - Silver and Copper Alloy
(Several die varieties exist)
REAL is currency used at that time (Spanish Real) More information on Spanish Real, refer here.
Circulated during the reign of Sultan Muhammad Jiwa Zainal Shah II (1710 - 1773)
Info collected from The Encyclopaedia of The Coins of Malaysia Singapore and Brunei 1400 - 1967 (by Saran Singh, 2nd Edition, 1996)
This piece is scarce to find and I am just lucky that someone offered me at a "reasonable" price.
Update 2012-July-17
More photo and information about the coin can be read at:
http://www.exonumi.com/?page=publish&id=1.127.CN.cb8be