Hi! My builder found several of these hardwood balusters for me (photo taken in direct sunlight). I would really appreciate some advice on how to clean and restore them. We're not sure of which type of wood was used, but I did the fingernail test and it's definitely a harder wood. One they're clean I will need to darken the wood to match the rest of the woodwork in the house, I think a walnut stain was used previously. I would prefer a natural finish, nothing too glossy. Thank you for your time