Reference for genuine examples: Malay Peninsula, Kelantan 10 kepings AH1321 (1904), tin When this denomination was issued, the coins contained a face value that was greater than the value of the actual tin metal content it contained. As is commonly the case in such a situation, counterfeiting quickly ensued. This caused the denomination to be withdrawn from circulation, leaving this coin as a one year type. More info and historical background can be found on the Malaysian Numismatic Blog: http://dniewcollectors.blogspot.com/2012/06/kelantan-10-keping-tin-coin-1321-ah.html The most quickly noticeable difference can be found in the design of the outer circle on both sides. On the contemporary pieces it has sets of 4 small squares (pics below), while genuine pieces have 4-petaled rosettes (pics on NGC site: https://www.ngccoin.com/price-guide...n-10-kepings-km-20-1321-cuid-34228-duid-99410). Other than that the style of the writing is more crude. This particular example is quite sharp and does not appear to have been circulated. It also has minimal white spotting, which is remarkable as tin coins from such hot and humid regions generally do not fare well.
Just wanted to comment and say that this is a great find! It's truly in superb condition for its age and material.
