Mobile Navigation

Diamond Sales

Petra sells all rough diamond production by method of open tender

Sales Process

  • At the end of each production cycle, the diamonds produced at our mines are delivered to our sorting facility, where they are cleaned and acidized, before being sorted into international sales assortments.
  • The rough diamonds are first sorted by size (carat weight) and then each size faction is sorted into quality ranges, depending on each stone’s colour and clarity. High quality larger stones or coloured stones are sold as single lots.
  • Individual mine production is kept separate, providing buyers with an additional level of knowledge about the goods they are purchasing based upon each mine’s unique diamond characteristics.
  • Tenders last between four to six working days, during which participants view the assortments and place a confidential electronic bid on the parcel of their choice.
  • At the end of the tender, the highest bidder wins the parcel.

The production profile (diamond quality and size ranges) of a kimberlite remains highly constant over time, resulting in accuracy for diamond price forecasting.  Our mines produce the full spectrum of diamonds, from low to the very highest quality and across a number of colours, including blue, pink, yellow and champagne. The image below shows a typical sales layout for one of our mines.

Diamond sales are typically weighted 40% FY H1 and 60% FY H2 due to the production cut-off in December around the festive season’s holidays. Petra adopts a flexible approach to diamond sales in order to achieve the best possible route to market, subject to prevailing market conditions and any COVID-19 related restrictions

Petra’s flexibility during the covid-19 crisis

During 2021 and 2022 we reduced the number of tenders to six from seven, although this had no impact on levels of sales.

See tender dates here

Sales Cycle


There are some key calendar events which impact diamond sales – see an overview of seasonality in the diamond market below (click to enlarge):


In this section


For enquiries related to diamonds sales, please contact:

Stephanie Hulett
Manager: Sales & Marketing

Johannesburg office: +27 11 334 0962

(Antwerp office closed until further notice)