This is a tin coin from Sultan Muhammed II era of Kelantan Sultanate. He became the second sultan in 1838 CE.
Circular tin coin ( pitis / keping) under the rule of Kelantan Sultan Muhammed II ( 1838-1886 CE) minted in 1256AH = 1840 CE.
Obverse : Karam Duriba Sanat 1256 ( The exalted. Minted in the year 1256AH)
Reverse : Khalifatul Mukminin ( Ruler of the faithful)
Weight : 6.7 gm
Rarity : Common ( ref SS11 pg 220)