I am looking to purchase a couple of used teak garden benches, which have historically had teak oil applied (look patchy now). As I prefer the natural silvering of the un-oiled look, if I was to leave these and not continue with oiling them, would the applied oil eventually disappear so the benches would then weather to silver? Is a de-greasing compound necessary? Or should I leave these and buy some that have never been oiled? Thanks in advance of your knowledgeable replies!