The Notre Dame's diamondThe fire that destroyed Notre Dame cathedral put us in front of a dilemma: would we like the same cathedral as before or a completely new one? We found the answer thinking about its history and Paris. Our project fits into the cathedral context, keeping the same external volumes prior to the fire. These are defined by ribs. They arise from the point left standing before the collapse, opening up like tree's branches, to support the vault's weight and as a sign of rebirth.We decided to use Lutheran limestone, which was used in the whole church and therefore also in the vault, to keep the same atmosphere. The use of the stone is original: it has been decorated by a floral pattern that allowed sunlight to go inside.The Gothic vault has been treated externally with the pre-existing material.The vault is interrupted where there was the spire. The spire will keep the same height, but it will have a new role:- during the day, it allows a greater illumination of the interior, accentuating the light on the altar;- during the night, it becomes a sparkling diamond, that you can admire from all the city.The recall is to Art Nouveau and Ville Lumi√®re. As woods sprout again from ashes, so Notre Dame cathedral will revive again, becoming the new diamond that will light up and will watch over Paris.