A fellow woodsy guy gave us a spatula made from butternut we use it for making porridge about 3 times a week. There is no finish at all and it has survived for many years, although it is discoloured from the blueberries that go into the porridge and the scraper part is a little tattered it still has years of use in it. We don't put it in the dishwasher nor soak for long periods , but rinse it off and let it dry.
I did read that a superior finish for wood utensils is a 3 or 4 day soak in watco oil then let hang for 3 months as that long of soak will need a long time to air out and off gas will make hard wood kitchen spoons preserve them under any conditions.
I have made strip type cutting boards from maple, walnut and basswood, used a mineral type oil or watco oil, applying several coats. with varying results but eventually warping, separating or cracking will happen under rough usage. Maybe watco oil is a mineral as I think from nuts of some kind.
