There are hundreds of tropical hardwood types that are used in woodworking. Some of the most common species are mahogany, merbau, okoume, teak, meranti, azobe and bangkirai. The sustainability profile of tropical hardwoods is characterised by good durability, but a large impact of transportation and risk of illegal activities connected to logging. Unless you are in the tropics or the wood is certified, you have to take into account that it is difficult to keep track of where the wood comes from. One of the main issues is that it could come from old growth rainforest.