LONDON – The world's top diamond producers will try to spur demand in India with the launch of their "Real is Rare" slogan in September, after the withdrawal of high-value bank notes dented the world's third biggest diamond market.

The marketing slogan was launched in the United States in 2016 by the Diamond Producers Association (DPA), which groups the biggest producers including De Beers, part of Anglo American, Russia's Alrosa and Rio Tinto.

DPA CE Jean-Marc Lieberherr told Reuters early indications were that the slogan was effective and diamonds had captured the interest of the millennial generation, which the DPA's research found wants "fewer and more meaningful things".

The Real is Rare slogan is intended to be international, but marketing campaigns will be tailored to specific markets with a DPA budget that Lieberherr said would see "a large increase" this year compared with last year's $12-million. He said he could not disclose the precise figure yet.

Research has been carried out in India into the culture of diamond buying there, the nation where diamonds were first mined and where activities such as diamond cutting and polishing employ more than a-million people.

Demand for diamonds in India slowed late last year following Prime Minister Narendra Modi's decision to scrap high value banknotes as part of a crackdown on tax evasion and counterfeiters. Most Indian people are paid in cash and buy what they need in cash.

After India, the ODA's next target will be China, the second biggest diamond market after the US Lieberherr is seeking to recruit an advertising agency in China with a view to launching the Real is Rare concept in China in April 2018.

The marketing phrase complements De Beers' A Diamond is Forever slogan, which dates from 1947 and is still used.

De Beers, the world's biggest diamond miner by value, said in an email it would release data for last year's diamond sales at the start of June, but it was already clear demand rose slightly last year driven by good growth in the US, which accounts for roughly 45% of global diamond sales.

China represents 14% and India 7%.

Anglo American has placed diamonds at the heart of its mining portfolio, saying they provide balance because they can hold their value as a luxury good even when basic commodities crash.