A sightholder is a company on the Diamond Trading Company’s (DTC) list of authorized bulk purchasers of rough diamonds. DTC is controlled by the De Beers Group, the single largest producer and purveyor of rough diamonds in the world. In May 2006, DTC released a list of the 93 sightholders on its website. ([1])
Eurostar Diamonds International ([2]) is one of the world’s largest sightholder.

References

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