Found 30 metres underground at a coal mine, they're dubbed 'Jurassic pearls' or the marbles of a Siberian colossus.
Giant natural balls in the Franz Josef archipelago that leave scientists flummoxed.
Nature makes its own collection of snowballs on the Arctic shore of the Gulf of Ob.
Like an approaching UFO, the bright white luminous ball glides over a field, before heading into woodland.
Stunning apocalypse scenes, as night turned to day in southern districts of the Republic of Khakassia.
Emergency services refuse to comment cause of extraordinary blast in the dark sky.
Expedition by leading chemistry institute finds area where it fell.
'If we die, I love you,' says one bather struck by bullet-like giant hail stones.
Mysterious 'gigantic' hole in remote region spotted by helicopters over gas-rich Yamal peninsula.
When Vadim Kolpakov went on an expedition to the north of Irkutsk region, he had no inkling of the sensational discovery he was about to make.