Unstable temperature and relative humidity, different rates of expansion and contraction, salt movement, living plant roots and other factors cause cracking in fossil wood. In order to prevent dirt and contemporary vegetation from accumulating into the cracks, and prevent breakages, solutions of especially prepared consolidants are injected in surface cracks. E. and Zouros, N. (2008) ‘Conserving the Lesvos Petrified Forest’, Studies in Conservation 53 (Supplement-1 - Conservation and Access: Contributions to the 2008 IIC Congress), London, p. 141-145 The beautiful rose colours of the silicified fossil wood in this picture are due to the presence of manganese ions.