Sure, teak can definitely be sanded though I've never heard of a teak veneer. Just be careful not to sand it too much, depending on how thick the veneer is. Also make sure you are wearing a good mask and are sanding it outside because the dust can be pretty bad for you. Then you'll need to use teak oil on top of it to show off all of the beautiful grains in it. We actually refinished a teak table that came out really great. If you want to see the video, which should give you a good idea of how to do it. Here's the link: From Bleak to Gorgeous Teak!