Jacob Ulrich Holfeldt Tostrup (1806 – 1890) is one of the best known Norwegian jewelers, silversmiths and goldsmiths. Tostrup was born in Norway to Nicolai Tostrup, an infantry captain, and his wife. He was the fourth of eight children. Between 1823 and 1828 he lived in Bergen, where he was apprenticed as a goldsmith

Widely considered one of the best Norwegian goldsmiths and silversmiths, David Andersen was apprenticed to the jeweller Jacob Tostrup in Christiania (now Oslo). During his apprenticeship he traveled to Berlin, Paris and London, where he exported the unique technique of the Norwegian filigree. In 1876 he was back in Christiania, where he founded his own company introducing his own mark, ‘David Andersen’.