David-Andersen (1843 – 1901) David Andersen established the workshop that now bears his hyphenated name in Oslo, Norway in 1876.  A fine gold and silversmith, he had a sense for quality and the high standard of his workmanship earned him success.
He expanded his operation into a steam powered plant and opened a second retail location in Oslo in 1892. When David died in 1901, his son, Arthur Anderson, took over management of the company. It was Arthur’s decision to hyphenate the family name.
The company’s pieces have been the work of many famous designers and the creations that bear the company’s mark, ”D-A NORWAY STERLING” and sometimes the full name, “DAVID ANDERSEN NORWAY STERLING 925S,” represent the finest in Scandinavian silver.
Their offerings include exquisite enamel jewelry and tableware accessories in silver and gold. The enameling is in many colors and applied over sterling. 
Natural patterns of leaves, insects, flowers, and animals are seen on many of the jewelry pieces. Among the designers who have produced items for David-Andersen include Bjorn Sgurd Oster, Synnove Korssjoen and Konrad Mehus.
In the 1930s, the David-Andersen company began using designer marks. The marks were rarely used on jewelry, but on larger enamel vases and bowls. In the 1960’s, the company started marking some jewelry with a designer’s mark. Normally the D-A designer marks have the abbreviation ‘inv.’, for inventor, and the initials of the designer.
In 1959, Uni David-Andersen, the great granddaughter of the company’s founder, began a small workshop of her own. Uni and her designers used the same system for designer marks as the family company. Jewelry from that workshop is typically marked both UNI and the designers mark.
The quality of a David-Anderson jewelry pieces (necklace or bracelet) is determined by the enamels’ durability. David-Anderson enameled pins, earrings, rings, and necklaces are still made today.
Their 1890s Dragon style plus Art Nouveau designs, jewelry designed in Art Deco, Art Moderne, and Modernism are collectible. David-Anderson is also famous for its Basse-taille leaf pins made in most jewelry styles and include bracelets, earrings, necklaces, brooches, and sets.