Silver rupee identification

Hi there, I have here a silver rupee, 18th century.  Obverse indicates emperor Alamgir. Diameter is 18mm and that seems odd: edges cut off maybe or is this a common size? Reverse: I can’t identify . Is it chinapathan? Patan or patna mint? how about rarety of this coin?
 

curious for your insights, best regard Dirk /holland 

It's a Rupee or ½ depending on weight, Bengal Presidency- Murshidabad, regnal year 5,  reverse like KM# 84.1,  part of zarb Murshidabad visible at the bottom

Hi, 

Update for your Coin request,

Mirza Aziz-ud-Din Muhammad (June 6, 1699 – November 29, 1759), better known by his regnal name Alamgir II, was the fifteenth Mughal emperor from 1754 to 1759. He was the son of Jahandar Shah.

Alamgir II  Silver Rupee, 

Murshidabad Mint , 

Weight : 11.00 - 11.60 Grams
KM # 460.15, ( South Indian Coins & Paper Money - Indian Edition - Page #136)

Rarity: Scarce

https://en.wikipedia.org/wiki/Alamgir_II

Regards - Anas / India / Qatar.

Thanks very much for your reply 

Dirk_Ypma

Thanks very much for your reply 

Your welcome