According to le Dauphine, he was walking with his wife in Grand Balcon Sud at an altitude of about 1,800 meters, above the Col des Montets.
A major landslide occurred on their way, the rocks ranging from the size of a microwave oven to that of a car.
According to Captain André Espinasse, new deputy commander of the High Mountain Rescue Team of Chamonix, the block that struck him was about 70 x 45 cm.
The hiker could not avoid the stones.
His wife witnessed the accident and called the PGHM, but the man was already dead when help arrived.
The PGHM in investigating the case to determine the precise causes of death.
Authorities in Chamonix have banned access to Col des Montets and Lac Blanc via the Lac de la Remuaz pass.
Because of the intense heat, the permafrost is warming and the rocks are constantly falling.
Last week a large landslide occurred at Cosmiques Ridge, you can read the article here.