Ancient slag is difficult to date. It has no organic material with which to perform radiocarbon dating. There are no cultural artifacts like pottery shards in the slag with which to date it. Direct physical dating of slag through thermoluminescence dating could be a good method to solve this problem. Thermoluminescence dating is possible if the slag contains crystal elements such as quartz or feldspar. However, the complex composition of slag can make this technique difficult unless the crystal elements can be isolated.