1911 Encyclopædia Britannica/Oligocene System
2021-7-21 · At the top of the lower Oligocene of this district is the lacustrine " calcaire de Brie " or middle t raver tine, which at Fertesous-Jouane is exploited for millstones; this is associated with the Fontainebleau limestone, which at Chateau-Landon and Souppes is sufficiently compact to form an important building stone, used in the Arc de Triomphe ...