In search of sources of Lime for UNESCO in Old Gorgora, Northern Ethiopia. Sites near to the former Jesuit monastery and Basilica on Old Gorgora, Lake Tana, have been listed, before, as a source of limestone, used from the beginning of the 17th century. But unfortunately, the area only contains basalt, lava flows and compressed volcanic ash with pumice inclusions, which has been used to form lightweight building blocks, but does not contain calcium carbonate. Nevertheless, a beautiful spot.