Tongkah Harbour Public Company Limited has engaged in various types of mining operations. Past performance of mining operations of Tongkah Harbour Public Company Limited group had engaged are as follows:

• Explored and operated offshore tin mining in Phuket province by sea dredge. By using the sea dredge in the mining,Tongkah was the first to use such technology in the world and the first company that own the sea dredge in Thailand.

• Exploration and operation underground gold mines at Ban Toh Moh, Amphoe Suirin, Narathiwat Province which the concession area is covered over 1,027 acres and it was a gold tunnel mining.

• Exploration and operation a gold mining in Khao Luang, Wang Saphung, Loei Province, in which the area covered over 1,291 rai. The area was a significantly anomalous gold and gold-base metal mineralization.