Rouble - Catherine I СПБ, portrait to the left

Catherine I ruled for just over two years following Peter the Great's death in January 1725, and the coins struck in her name at St. Petersburg reflect the administrative uncertainty of that transition. The SPB mint mark dates these pieces to the very beginning of her reign, before production shifted toward later portrait varieties. Catherine had no formal claim to succession beyond Peter's own decree — the first time a Russian ruler had ever named a spouse as heir — and the roubles struck under her name carry that political improvisation in their brief production window.

The .728 fineness was inherited directly from Petrine-era standards, never revised during her reign.