The steps are told in detail by Christie's in the featured post that accompanies the video.
The rough stone is extracted in Angola in February 2016. Weighing 404 carats, it is promising while being far from the records. Its quality is confirmed in New York by spectrography. For several weeks a team of experts researches the defects of the crystal.
Its bean form is not directly usable. In June, the world's best diamond cleaver with more than 50 years of experience cuts the stone in two halves from the middle. The polishing in emerald cut lasts six months, facet after facet.
They must now design a piece of jewelry highlighting this unprecedented wonder. The diamond is brought in December 2016 to De Grisogono in Geneva, which designs an asymmetrical necklace of emeralds and diamonds in 44 cm length. The jewel entrusted to Christie's then travels around the world before returning to Geneva for its auction sale.
SOLD for CHF 29.5M before fees