Coconut coir fiber generally has a golden color after cleaning and is hence, often called The Golden Fibe. Mature coir fibers are stronger than most of the other natural fibers such as cotton and flax. The coconut pith is also called peat or coconut dust. It is the material that binds together the coconut fibers in the outer shell of the coconut. Washed pith is a good choice as a growth medium in soil-less conditions for agricultural and horticultural purposes.