https://en.numista.com/catalogue/pieces63552.html
The weight says 12.09 grams and 0.864 fineness/composition. These are wrong.
The weight should be 12.9 g grams and 0.9 fineness. It has exactly the same weight and fineness as the 1897 15 ruble coin
https://en.numista.com/catalogue/pieces90655.html
They both say.
"2 Zolotniks, 69.36 parts of pure gold" on the edge
Russia devalued the ruble to 2/3 of its former value in 1897. They created the 15 ruble 1897 coin with the same weight as the previous 10 ruble coin (2/3*15 = 10 so a 15 ruble 1997 coin had the same purchasing power as a 10 ruble 1894 coin).
Also the 5 ruble coins coins from 1886-1894 weights 6.45 grams. and 2*6.45 = 12.9 so that's another confirmation that the older 10 ruble coin should be 12.9 g
https://en.numista.com/catalogue/pieces17819.html
