These coins have whats called security edge, that means the reeding should not be like on US coins, it should have a break in the middle and a series of circles or dots in the break.
Since you already have the Krause you probably know this, mine is from the 2010 issue, 37th edition KM# 555 1 Rupee Reeded Edge 1939(b) Dot, mintage 2,450,000 11.66g, 0.9170 silver, 0.3437 ASW F-$150.00 VF-$300.00 EF-$600.00 Unc-$1,200.00 KM# 556 1 Rupee Security Edge 1939(b) Mintage not listed 11.66g, 0.500 silver, 0.1874 ASW F-$200.00 VF-$400.00 EF-$800.00 Unc-$1,500.00
weight of the coin was from a hand held jewellary balance with me.I will recheck in electronic balance and post again.