A unique "gem-inside-a-gem" diamond thought to be over 800 million years old has been found in Siberia.
The "priceless" jewel weighs just 0.62 carats and is the first diamond of that nature to ever be found.
Inside, a tiny nested diamond moves freely and has an estimated weight of 0.02 carats.
The so-called "Matryoshka" diamond is named because it resembles traditional Russian nesting dolls.
The find - visible on X-ray - was announced by Russian diamond giant Alrosa and was made at the Nyurba diamond mind in the Sakha Republic, also known as Yakutia.
No value has been put on the one-of-a-kind discovery, which is likely to be 800 million years old.
Alrosa’s Oleg Kovalchuk told The Siberian Times : "As far as we know, there were no such diamonds in the history of global diamond mining yet.
"This is really a unique creation of nature, especially since nature does not like emptiness.
"Usually, some minerals are replaced by others without cavity formation."
This isn't the first time a rare discover has been made by the diamond mining group.
In July 2018, an unusual football-shaped diamond was found at the diamond mine belonging to Alrosa.
Experts described the unusual shape and pattern on the diamond as a "bizarre" natural creation
