RAPAPORT… A US advertising regulator has rebuked the Natural Diamond Council (NDC) over its environmental claims following a complaint by Diamond Foundry, a lab-grown producer.
The National Advertising Division, part of industry self-regulator BBB National Programs, has called on the NDC to stop using certain assertions that compare natural stones with synthetics, it said Thursday. These include statements that lab-grown diamonds emit three times more carbon than their mined counterparts.
The recommendation revolved around claims the Diamond Producers Association (DPA) — the NDC’s predecessor — first published in a 2019 report on the relative impact of the two products. In it, the DPA estimated the average carbon-dioxide emissions of its members at 160 kilograms per carat of polished, using data from 2016. That compared with emissions of 511 kilograms per carat for the equivalent lab-grown material.
“NAD determined that the advertiser’s evidence was not sufficiently reliable to support its comparative carbon-emissions claims,” it said. “Further, NAD was concerned that such claims conveyed a broader implied message about the overall environmental benefits of mined diamonds versus man-made diamonds, a message that was not supported.”
The NAD also criticized language that emphasized the increasing scarcity of natural diamonds, calling on the NDC to stop saying mined stones were becoming rarer by the day.
“[W]hile it may be likely that supply issues will someday influence the consumer market for natural diamonds, the challenged advertising reasonably conveys a message that consumers might become ‘priced out’ of the diamond market and unable to purchase natural diamonds in the future, and that they must therefore act now,” the NAD continued.
The NDC was not available for comment at press time. However, the NAD reported that the council had agreed to comply with the recommendations and that it would “incorporate” the suggestions “as it collects additional data to support its advertising claims.”
The incident marks the latest spat between the natural and lab-grown industries. Last month, the NDC complained to the NAD about Diamond Foundry’s marketing, prompting the watchdog to tell the synthetics maker to be clearer about the origins of its goods.
Image: A rough diamond and a polished diamond. (Natural Diamond Council)