Need help to confirm Mughal, Muhammad Shah - mint name [solved]

Hello,  the coin is  Silver  -  25.78mm  -  11.56g 

I am told it is -

Mughal, 1 Rupee - Muhammad Shah, Farrukhabad mint 

N#55607

However, I am not convinced on the mint and an image search doesn't give me an answer that fits.

Please help in confirming the coin is from Muhammad Shah and any assistance in identifying the mint will be highly appreciated.

Also, what is this mark (circled in red)?

It is on both sides of the coin. 

Thank you in advance

Maybe the Surat Mint instead: N#88004 although Regnal year 6 isn't listed.

I agree with rsirian1, it looks like the Surat mint to me. 

In Zeno there's an example with RY 4

https://www.zeno.ru/showphoto.php?photo=107559

And one with RY  8

https://www.zeno.ru/showphoto.php?photo=302998

So I think yours with RY 6 is reasonable.

Also checking Krause under KM#436.60 it does list RY 6 for these. 

The mark you are questioning may be a test/Shroff mark made by someone before accepting it to verify that it's solid silver and not plated, though yours is more detailed than most. 

Thank you rsirian1 and Seeker55, your help is much appreciated.

Fyi:   RY#6 has been added to N#88004

Seeker55

I agree with rsirian1, it looks like the Surat mint to me. 

 

In Zeno there's an example with RY 4

 

https://www.zeno.ru/showphoto.php?photo=107559

 

And one with RY  8

 

https://www.zeno.ru/showphoto.php?photo=302998

 

So I think yours with RY 6 is reasonable.

 

Also checking Krause under KM#436.60 it does list RY 6 for these. 

 

The mark you are questioning may be a test/Shroff mark made by someone before accepting it to verify that it's solid silver and not plated, though yours is more detailed than most. 

The reason I asked re the mark is because I had not seen such a nice (detailed, as you put it) Shroff mark before.