If you ever get offered teak for free, you have to grab it - even if you don't use it for woodturning.
It is awfully dense, though, and not easy to turn and you will need to sharpen your tools often. Nevertheless, you should look for opportunities to use it outdoors such as bird houses, finials, etc. Just be sure it isn't Ipe which looks like teak and has similar properties. When you turn it, though, the shavings come off as fine yellow dust that carries from the shop into the house and is really bad for you if you inhale it.