Back to the story of the Borodin ruble, here is an example of such coins in Yale University collection.
http://www.library.yale.edu/slavic/coins/h...274_267.html#obNotice how similar the 1834 ruble and 1839's design of Alexander I are similar.
And here is a blown-up image of my 1834 rubles and the 1839 ruble together. Sorry, I don't have the coins with me or I would have retaken more photos.
http://img9.imageshack.us/img9/3808/34394hq.jpgNote: 470kb
The only thing I remembered that the diameters of all of them VARIED by a few macrometers

As for the Borodin ruble, some odd things that I remembered was the oddity of the color, but it could be toned so I cannot tell. As for now, I guess I have to work out from the pictures available.
As for quite a fair bit of Borodin rubles that I have seen, at least 5 by now, most of the decent fake rubles have almost perfect reverse (i.e. the monument side) due to it's simplicity. Of course, as I haven't seen a real Borodin ruble, I can't quite tell except to compare the portrait of the Alexander I against the genuine ones that I have.
The real trouble with the obverse is with Alexander I's hair and the signature of Gube. F. which is found at the base of the collar. Very often with counterfeits, it seems that the hair of Alexander I's are struck too weak or often modified till you get "spagetti" hairlike features like the first coin I have mentioned here. My best guess is that when the "weak" hair structure got worned out over striking several counterfeit coins, they were re-engraved so that they could "feature" more hair, but then you get distorted features.
As such, I believe that this coin could be a "high-end" counterfeit.