The firm "K. Gan" was founded in 1873 in St. Petersburg, Russian citizens of Austrian origin Karl Gan.
Upon arrival in St. Petersburg, Karl Hahn settled in the house of the Swedish Church on Malaya Konyushennaya, and opened a store on Nevsky Prospekt, at number 26.
The assortment of products of the "K. Gahn" workshop was quite impressive and consisted of gold and diamond items: cigarette cases, ashtrays, cups and "various other works of art with enamel" which were of high quality and were in great demand. The development of the company made it possible to take part in the World Columbus Exhibition in Chicago in 1893. Two years later, for the high quality of his products and the successful fulfillment of orders from the imperial court, jeweler Karl Hahn was awarded the title of supplier of the Imperial Court. In 1896 he was appointed an appraiser at the Cabinet, and soon received the Order of St. Stanislaus of the 3rd degree and the title of hereditary honorary citizen. In 1893, Karl Hahn′s jewelry workshop was a manual production, which employed 30 workers, and its annual turnover reached 100,000 rubles.
By 1899, Hahn owned two tenement houses, another house belonged to his son, the merchant of the first guild Karl Karlovich Hahn, who was rightfully considered the most serious rival of Faberge.
From 1892 to 1909 the jeweler KK Blank worked in the firm, and from 1909 to 1911 was a partner of the firm "K. Gahn", but after the death of DK Gan the firm ceased to exist. The fixed capital of the Partnership in 1909 was 50,000 rubles. The firm has done a lot of things for the Cabinet of E.I.V., specializing in orders with diamonds and other items with precious stones, as well as enameled cigarette cases. The items made of gold and silver, made by the company′s craftsmen using enamels of a wide range of colors, were distinguished by their elegance of form and a great sense of stone.