Second, De Beers is the undisputed Sales of rough diamonds price leader. (called"sights") are managed by the CSO to an exclusive group of cherry picked" merchants(kn own as sight holders") from cities such Johannesburg, Mumbai, New York, and Tel Aviv. Sightholders would inform the CSO of their preferences for quantity and quality. The Cso then matched them with inventory. During each sight, the Cso offered each sightholder a preselected parcel. The buyer either took it or left it-no bargain ing was permitted. Buyers usually took the parcel. If buyers did not like the system, they would be not invited again. This tactic allowed De Beers to control, down to the carat, exactly what and how many stones entered the market and at what price. To maintain the exclusivity of the sightholders, their number was reduced from approximately 350 in the 1970s to less than 100 sightholder in the 2000s.