1551 https://demo.fonds-documentaire.fr/detail.php?inventaire=1551 Ardoise, extraction et fabrication, planche - Slate extraction... EN NOIR & BLANC Wikimedia Commons 2011 image jpg fr Notice iconographique issue de Wikimedia Commons. Titre: Ardoise, extraction et fabrication, planche - Slate extraction, historical, in France, plate with line illustrations, etc. - Public domain illustration from Larousse du XXème siècle 1932. Ardoise, extraction et fabrication, planche - Slate extraction, historical, in France, plate with line illustrations, etc. - Public domain illustration from Larousse du XXème siècle 1932. Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional metamorphism. Éditions Larousse is a French publishing house specialising in reference works such as dictionaries. It was founded by Pierre Larousse and its best-known work is the Petit Larousse. iconographie illustration gravure patrimoine wikimedia commons Iconographie Estampes et illustrations Vidéos Youtube - Histoire et patrimoine Wikimedia Commons https://commons.wikimedia.org/wiki/File:Ardoise,_extraction_et_fabrication,_planche_-_Slate_extraction,_historical,_in_France,_plate_with_line_illustrations,_etc._-_Public_domain_illustration_from_Larousse_du_XX%C3%A8me_si%C3%A8cle_1932.jpg Licence Creative Commons Zero, Public Domain Dedication via Wikimedia Commons https://upload.wikimedia.org/wikipedia/commons/0/09/Ardoise%2C_extraction_et_fabrication%2C_planche_-_Slate_extraction%2C_historical%2C_in_France%2C_plate_with_line_illustrations%2C_etc._-_Public_domain_illustration_from_Larousse_du_XX%C3%A8me_si%C3%A8cle_1932.jpg