Because it is so readily made by heating limestone, lime must have been known from the earliest times, and all the early civilizations used it in building mortars and as a stabilizer in mud renders and floors.[3] According to finds at 'Ain Ghazal in Jordan, Yiftahel in Israel, and Abu Hureyra in Syria dating to 7500–6000 BC, the earliest use of lime was mostly as a binder on floors and in plaster for coating walls.[4] This use of plaster may in turn have led to the development of proto-pottery, made from lime and ash.[4] In mortar, the oldest binder was mud.[4] According to finds at Catal Hüyük in Turkey, mud was soon followed by clay, and then by lime in the 6th millennium BC.[4]