Contact Edensaw Woods for product pricing and availability 1-800-745-3336 Cumaru has high durability and is resistant to rot and weathers well. An excellent choice for a deck project. The heartwood is medium to dark brown and sometimes has a reddish purple hue. Unlike most other woods Cumaru tends to lighten with exposure to light. Due to its density and interlocked grain. Cumaru can be surfaced planed to a smooth finish, and also turns well on the lathe.