Koller Auktionen

Koller is one of Zurich’s leading auction houses and holds four jewellery sales a year, drawn mainly from private collections and covering coloured stones, diamonds, natural pearls and jewellery from all periods. Signed pieces turn up regularly, from Boucheron, Bulgari, Cartier, Harry Winston, JAR, Mauboussin, Tiffany & Co., Van Cleef & Arpels and Webb, so period rings appear across a wide range.

Specialists weigh each piece on both its history and its design and assess market value with provenance and collectability in mind. If you want to consign, valuations are free, and the house runs appraisal days across Europe in cities such as Milan, Lugano, Düsseldorf, Munich and Geneva. Beyond Zurich it keeps representatives in Geneva, Munich, Düsseldorf, Florence and Beijing, and the site is available in English, German, French, Italian and Chinese.