As recently as August of 2017, De Beers publicly refused to allow its rough diamond producers to offer information on their supply chains to retail, as reported by JCK.  

De Beers Senior Vice President of sightholder sales (De Beers’ list of authorized bulk purchasers of rough diamonds) sent his clients a note stating: “Several [sightholders] have contacted us recently by requesting permission to confirm to supply chain partners that specific goods originate from a primary De Beers source….We have declined all such requests.”

It is not entirely clear why De Beers chose this path, as it seems to fly in the face of consumer desire for more transparency. The note is specifically in response to the GIA’s Mine to Market app. The app - which De Beers declined to join - attempts to bring clarity to gemstone origins. De Beers claims that being part of the GIA’s program will “create confusion in relations to [retail chain] De Beer’s Diamond Jewelers.” It further claims that there are other tools that inform customers of the provenance of their goods.

Like most things in the mined diamond industry, it seems there is more to this than meets the eye.