(IDEX Online) - De Beers is preparing to stockpile more unsold diamonds after this week's sight in Gaborone.It is expected to offer sightholders smaller allocations than usual, with rough prices showing no sign as yet of picking up, and to hold onto more stock as a result. "We build up stocks of those because we are confident that over time the diamond price will increase and we will be able to sell that supply into the growing demand that we believe will come," CEO Al Cook told a briefing in Gaborone, as reported by Bloomberg.Last month the UK-based miner said its full-year production forecast for 2023 would remain unchanged - at 30m to 33m carats - despite a 23 per cent drop in its Q3 output.November sales (cycle 9) crashed to just $80m, the lowest figure since it started reporting sight totals in 2016.The current sight, the last of the year, concludes on Friday (8 December) and is not expected to bring in more.