Villetaneuse (France) (AFP)

To "push" in a few weeks diamonds identical to those extracted from a mine, and cheaper: this is the successful challenge of a start-up located north of Paris that is preparing to step up production, taking advantage of the breakthrough of laboratory stones in the jewelery market.

In a room cluttered with noisy machines, two engineers observe through a porthole five small mounds that glow in a thousand-degree oven: it will take them between three and six weeks to become diamonds, while the average age of the gems formed under land is a billion years old.

"Diamond is only carbon, so we create the conditions for carbon to be deposited atom by atom, and diamonds grow like cakes!", Summarizes AFP Alix Gicquel, 64, president of Diam Concept, housed in a CNRS laboratory at Paris 13 University.

This researcher has 30 years of work behind her: in 1987, at a conference in Japan, she discovered that we can create diamonds through "plasma" - this fourth state of matter with the solid, the liquid and the gas, which is precisely his subject of study.

"In 1990, I went to the CNRS for a research team and quickly made diamonds for scientific applications, but the real challenge was to be able to produce the whitest stones possible, and thick enough to be used. in jewelry, "explains Alix Gicquel.

She rolls in her hand an orange stone that shimmers in the sun: "It's one of my favorites, it's 2.38 carats, white diamond is produced, but it can be colored by adding nitrogen".

The technique used by Diam Concept consists of placing diamond slats in a "reactor", a sort of microwave oven where hydrogen and methane are introduced which, at very high temperatures, crystallize layer by layer the carbon atoms, until to form a rough diamond.

The company presents itself as the only one in France to create laboratory diamonds for jewelery. American, Russian and Chinese companies are already producing synthetic stones, whose prices are 30 to 40% lower than that of mineral diamonds.

- "the diamonds of the future" -

For Alix Gicquel, there is no doubt: "the laboratory diamond is a bottom blade, it will explode".

In French jewelery, these gems are still confidential, although the general public brand Maty launched last year a collection of synthetic diamonds.

"In 2018, 6% of solitaires of more than 0.3 carat sold in France were synthetic, but for the diamond jewelery market as a whole, this proportion is less than 0.5%. says Hubert Lapipe, CEO of Company 5, which provides data for the annual report of the watch and jewelery sector.

Diam Concept, which is expected to sell a hundred diamonds in 2019, believes it has sufficiently stabilized its process to intensify its production: the five-person team is about to join the Air Liquide group's innovation center.

"We will multiply the + reactors, make larger batches and equip ourselves with a laser to cut the stones ourselves.We have already won a lot of grants and are preparing a major fundraising," enthuses Alix Gicquel.

She is eager to meet the demand: "We have calls from all over the world, from jewelers, wholesalers and individuals ... For now all the diamonds are reserved, but it's clear that we already have our future customers! ".

His speech is far from delight mining groups, which before this new competition have invested this year no less than 60 million euros in communication to promote the "unique" character of the stones extracted from the earth.

"We make diamonds, point, with the same properties as theirs, ethics in addition, and with a low carbon impact", puts forward Alix Gicquel.

"I am not at war against the diamonds mines, but for me it is the diamonds of the past, and our diamonds are those of the future", summarizes the researcher whose hands are adorned with two rings, one in natural diamonds , the other set with a laboratory diamond.

© 2019 AFP