By 1827 , the Russian treasury had accumulated large reserves of platinum , extracted from the Ural mountains .
Platinum coins were minted in Russia in the middle of the 19th century , they were sometimes called white or Ural chervontsy .
By 1827 , the Russia treasury had accumulated large reserves of platinum , extracted from the Ural mountains .
Platinum coins were minted in Russia in the middle of the 19th century , they were sometimes called white or Ural chervontsy .