Colla Wood is a petrified wood that only comes from Turkey. A father and son mining team discovered this material in 2012 while prospecting for other minerals. Petrified wood itself is not uncommon, however the trees that this material comes from were located in an active copper deposit. As they decomposed, the copper bearing minerals seeped into the decaying matter and replaced the organic wood. Colla Wood is incredibly rare, especially the specimens containing any of these copper minerals: gem silica, chrysocolla, azurite, malachite, volborthite and tenorite. This is probably the top 3% of this material.. We have had 100s of kilos and very very little of this even comes close to this.