Bio-composites have attracted considerable attention due to their low cost, bio-degradability and potentially sustainably renewable nature. This is especially the case for those bio-composites whose components are free from competition (moral and economic) from other sources, especially food crops, or environmental damage. There are abundant ways to preserve the environment together with the development of new composite materials. The available waste from the food industry that comes from marine animals is composed of very large amounts of endo- or exo-skeletons. These consist of calcium carbonate (CaCO3) or chitin and can be used as reinforcing fillers for natural rubber. Under optimal curing conditions and filler levels, green CaCO3 derived from cuttlebones could provide improved mechanical and biodegradable properties to NR vulcanizates as the non-green commercial CaCO3.