I have a strong sensitivity to chemicals, so I have been trying to figure out what to use on them. I looked into low/zero voc finishes and discovered that they were just too expensive for the amount of floor space I had to cover, so I decided to give olive oil a try.
I read quite a while ago about making a furniture polish from vegetable oil and lemon juice (the lemon juice smells good and is supposed to help keep the oil from going rancid). I didn't want to use vegetable oil because most (unless they are organic) are made from GMO corn or soy beans, and I don't want to support that industry. That is why I decided to try the olive oil (plus I had some here and didn't have to drive to the store).
I poured some oil into a used yogurt container and added a few drops of lemon essential oil (again, because I had some here) and got started. I used a rag and applied the oil on my hands and knees, but I think a sponge mop would work fine. The night before I had done a small spot to see how it would be after sitting over night. It looked great.
It took me about a week to do most of the house (I still have a little more to do) because I did just an area at a time. I didn't want to have to move large pieces of furniture (huge cupboard in the kitchen), so I just went around them. If I move them at a later date I can do the floor then. That's the beauty of using oil, you can patch places here and there and it will blend in.
I am not sure how long the finish will last, I may have to do it every 6 months or so, but it will be worth it. The floors look beautiful. They have the look of an old cutting board with wonderful patina.
Before and After:

