Scarwood

Scarwood is a special type of wood that is harvested from scar trees in the Forest of Many Scars. Entirely black in color, it is more resistant to flames and axes than regular wood, making it particularly useful for construction materials. Furthermore, while some druids find it abhorrent to use wood that was effectively created from fire and war, it is an excellent material to construct protective armor that does not contain any metal.

[DnD 5e] Game mechanics

Armor can be created out of scarwood, and such armor is sold in Siarvald and Qarah's Dream. Such armor costs 300 gold + the price of the normal armor. Any light armor and any medium armor can be found in this form. Druids can wear scarwood armor with no penalty.   Armor made out of scarwood provides resistance to fire and slashing damage, and counts as an uncommon magic item.