Daumet white gold is an innovation that is far from trivial. It could, in the long run, change the jewellery supply in depth.
A few reminders to understand
Title, alloys, and colors
The title is the proportion of fine gold (24 carat gold or 100%) in an alloy. Historically, we’re talking about « carats. » Since 1995 it’s indicated in thousandths. 18-carat gold, for example, is 18 carats of fine gold on 24 or 75% or 750 thousandths. I’ll let you redo the calculation to better unederstand. It’s a basic ruel of three.
But why add 25% of one or more other metals, in short, why alloys? 3 reasons for this, two of which are mostly technical and the third aesthetic.
- Lower the melting temperature
- Increase the strength of the metal because the gold is very smooth, very malleable and therefore very easily deformable when it is pure.
- Change the color: native gold is yellow.
The colors of gold
The difficulty lies in the fact that 75 of the metal is very strongly yellow. There are only 25% metal left to change the color. In the chart below are the main gold alloys obtained by smelting different metals: There are different titles (proportions of pure gold), I choose 18 carat gold for my explanations because it is the alloy that is used in jewelry.
The difference between the two yellow golds comes from the proportion of silver and copper. as far as pink and red gold are concerned, the solution is the same. With regard to « grey » or « white » gold, there is to this day an alloy with nickel, abandoned as an allergen and palladian grey gold. The alloy with palladium as shown in the table above, in jewelry, is almost always covered by electrolysis with a thin layer of rhodium that masks the true color of the base alloy. This is because the alloy itself, retains a hint of yellow in the color.
In watchmaking there is un rhodiated palladium grey gold. This is the choice of Rolex for example. You have to see it to understand, the photos are not very telling.
Gilding, gold-plated and vermeil
In all three cases it is an electrolysis deposit of different thicknesses of gold (we are talking about micron thickness). The plating and gilding are electrolysis deposited on a common metal such as brass and vermeil on solid silver. Which leads us to understand why there was no white-plated gold. And for good reason, it would take two successive layers of metal by electrolysis: first the gold alloy and then the rhodium. That’s why there are fancy jewelry in yellow or pink gold plated and a silver version to feature white metal, white gold. That was without counting on Cyrile Deranlot.
Daumet white gold: first revolution
It is in fact in this context that Daumet’s discovery comes into the game. There is no need to dwell on the spintronics that has led to the search for a particular material. What interests us is the chance discovery of a very « white » alloy by association of 750 thousandths gold with 250 thousandths of Tungsten and, to idea Cyrile Deranlot, CEO of Daumet, who saw it as an application in the jewelry sector. This alloy not only does not require rhodiating but is obtained, not by fusion, but by cathode spraying, in short, a result equivalent to plating.
Many access jewelry brands should turn to this innovation which, moreover, is eco-responsible because it does not require the use of acids. Combining white plated gold with gold plated in traditional but eco-responsible colour is a win-win on all. Not to mention the fact that tungsten is much cheaper than palladium and rhodium. And furthermore, tungsten is 1 million times more abundant in the Earth than gold, palladium and rhodium. To extract it, it requires carrying less ore, which greatly reduces the environmental impact.
But the discovery doesn’t end there.
The gilding of organic materials: the second revolution
The Daumet technique, dry and chemical-free, covers leather, feathers, wood and textiles, preserving the original texture of the material, its hand and its smell. It is easy to imagine Hermes or Boucheron revisiting, one the Niloticus with skin and the other the eternal flowers, and this hand in hand with Daumet.
It is easy to imagine from these flowers and a few tricks a pair of golden earrings by Daumet carriing in his heart real flowers.
Massive white gold: a third potential revolution
For my part, I look forward to the next step that would revolutionize solid 18-carat white gold: Solid Daumet White Gold. Indeed, the rhodiage of white gold does not withstand over time. Thus, white gold jewelry is the subject of an eternal after sale service to redo the rhodiage. And the operation is not a 10 seconds opreation, it is necessary to remove the remaining rhodium on the jewel, clean and repolish the jewel and then redo the rhodiating operation. This means extra costs mostly at the expense of the brands that offer it to their customers, not to mention the time spent.
But the game is not won because solid white gold requires the fusion of gold and tungsten and tungsten has a very high melting point. Probably this difficulty is not the only one. Let’s keep our fingers crossed that Cyrile Deranlot’s research will be quickly successful.
Case to follow, as usually
Below is Cyrile Deranlot’s Pitch just in case.