I have a couple of heavy contemporary square coffee tables (meant to be used together), originally purchased at W & J Sloane through a decorator, that we've kept in our barn for about 40 years. I'd like to clean them up and try to sell them, but want to make sure I don't ruin the wood (oiled walnut) or in the process.

I also need to be careful of the bottoms, which are made of some sort of rattan or caning in an even weave.

My son says the pieces are veneered. I didn't think so, but he's usually right about these things. They're very heavy, though.

Any thoughts? Many thanks!