Teak oil and what it actually does
Teak oil is the most misunderstood bottle on the shelf. It is not pressed from teak, it does not feed the timber, and it is not one formula. Most tins hold a thinned blend of a drying oil, usually linseed or tung, with a varnish component and a solvent to make it flow.
What it does is soak a short distance into the surface fibres and then cure there, hardening in contact with air. The result is a finish that lives just below the surface rather than sitting on top of it as a film. That is why an oiled piece looks like wood rather than like a wood-coloured sheet of plastic, and it is why oiled surfaces mark so easily.