Dmitri Osipov was a Russian jeweller and goldsmith based out of St. Petersburg, who created pieces for the House of Faberge along with many orders and decorations.
Osipov was a joint owner of the ARND. Jewelry Company with Johann Hellwing Arnd from 1890-1900. He then owned the company outright from 1902 until selling to Andrei Karlovich (A.K. Adler).
The markers mark stamp is “ДО” (“DO” in Cyrillic).
The Imperial Order of Saint Anna was a Holstein ducal and then Russian imperial order of chivalry. It was established by Karl Friedrich, Duke of Holstein-Gottorp, on 14 February 1735, in honour of his wife Anna Petrovna, daughter of Peter the Great of Russia.
Originally, the Order of Saint Anna was a dynastic order of knighthood; but between 1797 and 1917 it had dual status as a dynastic order and as a state order. Membership of the Order was awarded for a distinguished career in civil service or for valour and distinguished service in the military.