Platinum Roubles

The average reported weight for the 3-Rouble 'Ducat' was 159.776 Grains (~10.353 Grams), probably a fair estimated value for lightly circulated coin.

In France, the estimated weigh for the1828/30 coin was ~10.364 Grams.  


Reported in 1843, the Weights of Platinum Roubles, from a Russian collection/publication; updated in 1855: the 3-Rouble of 1833 weighed 159.11 Grains; the 1834 weighed 160.19 Grains.  The annual Average Weight is ~159.81 Grains (10.35553 Grams)

Citation: Monnaies et médailles russes, d'après l'état donné par le cabinet du General D'Infanterie...,  Fedor Fedorovich SHUBERT (1858)

1788

1788: 1 Troy Oz. Silver (UK, .999 Mkt) = £0.2904 ; 1 Troy Oz. Silver (S$ .999) = £0.2941

1788 France/UK Exchange:

£ 1. = L.T. 22.7692?


Where the Paris Ell was 1.213 English Yards, and '24 Livres' (Louis d'Or) = £ 0.9286, so 
"33 L.T./Ell" = £ 1.306 ∴ 1 English Yard of 'Peignon' cost 27.205 L.T. (=£ 1.08) 
 
In 1802, the London Price was £ 1.575




1788: S$1. = £0.1750?