FRANCE. CHAMPS SUR MARNE. 08th of october 2019. LRMH ( Laboratory of Research of Historical Monuments ). Research on several elements coming fron the burning of Notre-Dame cathedral. Aurélia Azema ingeneer of studies of the metal pole. She is observing through an electron microscope (microscope electronique à balayage) samples of lead dust taken from a tube of the cathedral organ organ. Elemental carthography where each color (fictive) corresponds to a different element. The more intense it is, the more present will be this element in the sample.