The treasures fell out of a loose hatch in the plane’s hold.
Precious metals and diamonds rained over the runway and a swathe of Yakutia, the coldest region in Russia.
The hatch door fell off near a car market without causing injury.
The plane bound for Krasnoyarsk then made an emergency landing at Magan after discovery it had been haemorrhaging valuables.
The nightmare happened on takeoff from Yakutsk, the regional capital.
“The Nimbus Airlines AN-12 cargo plane hit problems during takeoff and the treasures fell out of the hold all over the runway,” reported The Siberian Times.
“The plane plane then dropped some bars of gold as far as 15 miles from the airport.”
Police sealed off the runway and a vast search is underway.
Only secret services operatives are allowed to take part.
It is unclear if it was an accident or a deliberate attempt at a ring heist.
Technical engineers at the airport who prepared it for takeoff have been detained.
“They are undergoing interrogation,” said a source.
The cargo belonged to Chukota Mining and Geological company.
Some 75% of shares belong to Canadian Kinross Gold.
Yakutsk is capital of Yakutia or the Sakha Republic, Russia’s diamond producing region.