Blocks of Jurassic pearls change color when it rains in Siberia

Located under a Siberian mine 30 meters from the ground, strange round round stones are called "Jurassic pearl" or "giant marble".

According to The Siberian Times, ten stone globes are about half the size of adults and about a meter in diameter, round and smooth.In particular, their colors change after it rains.

The adjacent spheres were found by an excavator at the Sereulsky coal mine in Nazarovo district of Krasnoyarsk, Siberia.

Experts exclude the possibility of human-generated spheres and affirm that they exist since Jurassic.

These strange stone globes are formed by a natural process similar to that of pearls.

Known as a ganglion, the stone spheres form on sedimentary rock due to the deposition of large amounts of organic materials such as leaves, shells and fossils around a hard core.

"The spheres form in a way similar to pearls, when a grain of sand gets inside the son and it tries to push the sand out. Water flowing through sedimentary rocks leaves many minerals that help bind sand, mud or "The other masses are huge. These blocks are very rare," said Olga Yakunina, a scientist at the Central Siberian Geological Museum.

The reason their color fades after it rains is because of the iron oxide in the composition.