The family-owned firm moved to Bruton Street earlier this year, ending a 144-year presence on Bond Street.
Sotheby’s will offer 260 lots on October 18 from the venerable dealership.
Nicolas Norton, director of SJ Phillips and great-grandson of the original founder, said: “Earlier this year, we moved to… the second floor of 26 Bruton Street… Owing to the smaller space, we are no longer able to display all of our collection successfully and have decided to part with a number of beautiful objects.”
Some of SJ Phillips’ high profile clients have commented on the decision to sell part of the stock of the upmarket jewellery firm.
Dame Anna Wintour, editor-in-chief of Vogue, said: “It will be thrilling to see so many of the Nortons’ exceptionally beautiful and highly curated treasures find new homes.”
David Bennett, Sotheby’s worldwide chairman of the international jewellery division, said: “Spanning over a century of jewellery design, this sale offers collectors an opportunity to acquire timeless pieces, rich with the charm and romance inherent in vintage jewels."