A "new Siberian metal", platinum, became known in Russia in 1819. Though it was first observed only as minor inclusions in rocks, richer deposits were discovered in the late 1824 which were mined beginning in 1825. These discoveries prompted Demidov to start looking for platinum around his Nizhny Tagil plants, where it was quickly found along the river beds. In late 1826, P. G. Sobolevsky (the father of powder metallurgy in Russia) invented a simple way of processing platinum that prompted the idea to use platinum in coins. The decree of 24 April 1828 noted that "among the treasures of the Ural Mountains also occurs platinum, which priorly was located almost exclusively in South America. For easy sale of this precious metal, it is desirable to introduce it in coins" and also described the design of new coins.