Almost unbreakable, this rock constitutes much of the crust of our continents and the root of our mountains. This rock, considered as the base of the terrestrial world, is granite.
This rock is recognizable by its white color; the great builders have chosen it for their most edifying monuments. But even more surprising, it is born from the living and has maintained a filial relationship to it.
Clay is a particularly surprising rock. Soft and fragile when dry, it is malleable when in contact with water and can freeze permanently under the action of fire.
