Selling & Buying


Since the launch of the consultancy in 1999 John C Benjamin Limited has been instructed to sell an extraordinarily diverse range of antique and contemporary jewels, diamonds and gems on behalf of private clients in the UK and overseas.  Highlights include:-

  • A 2.97 carat fancy greyish-blue diamond ring by Andrew Grima (a world record price in 2015)
  • An historical diamond weighing in excess of 100 carats
  • A superb 9.61 carat Kashmir sapphire ring
  • An important collection of rare and historic 17th century jewellery with Royal associations on behalf of a noble family
  • A Boucheron Burmese ruby and diamond ring
  • An impressive 14.24 carat diamond ring

It should be stressed that the consultancy is not a dealership and therefore does not carry any stock. All consignments are sold on a “commission only” basis either by private treaty arrangement to a range of well- established London dealers or by disposal at international auction. Indeed, since 2015 the consultancy has successfully sold over £3.25 million of jewellery consignments through one leading international auction house.

Favourable rates of commission are negotiated at the outset and, beneficially for all vendors, John C Benjamin Limited’s own commission is paid directly by the nominated auction house.  All consignments are fully covered for insurance purposes under Hiscox’s all-risks policy.


Whether buying a diamond engagement ring, a rare antique jewel, a fine precious gem or a special gift for a birthday or wedding, John Benjamin will resolve your particular enquiry quickly, discreetly and at a decidedly competitive price. Items bought on your behalf are invariably made through established trade suppliers or at auction so you can feel confident that you will not be paying a “Bond Street” retail mark-up. All purchases are accompanied by an insurance valuation giving a detailed description of your jewellery.

Commission For Buying Jewellery
10% plus vat of the actual cost price.
Large or unusual commissions are subject to individual negotiation with the client.

Helping You To Buy, Sell and Value Antiques and Fine Art
John Benjamin has built up an excellent network of contacts in the antiques world through dealers, auction houses and independent valuers. Please contact us via or telephone +44 (0)1296 615522 if you require advice and help relating to the purchase, disposal or valuation of paintings, furniture, silver, works of art and ceramics.