The shoe-box size metal container with emeralds, rubies and sapphires neatly packed into sachets, some marked 'Made in India', was discovered off Mont Blanc in the Alps.
The historic haul, valued by French jewellers at around 205,000 pounds, is believed to have belonged to someone on one of two Air India flights that crashed off the world-famous mountain in 1950 and 1966, killing over 100 people.
French media reported that if an owner is not found, under French law, the jewels could be given to the climber, who was not identified by the authorities.
French officials have praised the mountaineer's honesty after he immediately reported the find to local police.
More From This Section
"This was an honest young man who very quickly realised that they belonged to someone who died on the glacier. He could have kept them but he preferred to give them to the police," local police chief Sylvain Merly was quoted as saying by The Guardian newspaper.
Last year, two climbers on the glacier discovered a well-preserved bag of Indian diplomatic mail neatly marked "Ministry of External Affairs" that had been on the Boeing 707 flight from Mumbai to New York that crashed near the summit of Mont Blanc in January 1966.
That crash killed all 11 crew and 106 passengers, including the pioneer of India's nuclear programme, Homi Jehangir Bhaba.
The cause of the crash was never fully established but the mail bag, found 46 years later by a mountain rescue worker and a fellow climber in 2012, was handed back to the Indian government.
Mont Blanc, hailed as one of the world's most beautiful mountains, has a history of dangerous storms and fatal avalanches.