Danish Silver
Under the Danish Hallmarking Act of 1893, the content standard for all silver was set at 826 parts out of 1,000, which is slightly lower than the standard for sterling which is 925. The remainder is usually copper with very small amounts of iron, lead and traces of other metals. The Danish mark, 826S was used until about 1915 when silversmiths raised their silver content to 830 and eventually to 925. Georg Jensen did not switch to the sterling standard until 1927 although he occasionally made special orders in 925S for the American market much earlier.
Until 1961, Danish silver was identified by a stamp with three towers. After that an 830S or 925S imprint was used. (A mark with two towers means silver plate.)