If left untreated, teak wood, also known by its Latin name Tectona Grandis, has a life expectancy of 75 years. This dense grained hardwood is impervious to the effects of snow, rain, sun and ice and has for centuries withstood the test of time when used as key components in shipbuilding. The high level of resinous oil and rubber content in teak also acts as a natural parasite repellent making it virtually immune to rotting, and will last you generations without any special treatment.

This stool is from GREENtoko warehouse:

http://www.loveteak.com/