As reported before, washed coconut fiber contains a high lignin and holocellulose. Lignin acts as the cementing agent in fiber, binding the cellulose fibers together. Cellulose is the primary constituent of fiber. Ratanakorn et al. reported that the bulk content of lignin and celluloses remained constant, while inorganic compounds can be removed by washing coconut fiber. For both EDS spectrums it can be seen that carbon and oxygen still present in coconut fiber. Washed coconut fiber is stiffer and tougher, and therefore improves the density of cement panel.