On Saturday, September 8, 2018 at 9:33:21 AM UTC-5, Ivan Vegvary wrote:
Cut a very detailed threshold out of 1x6 oak board. As it turns out the color of the board is perfect complement to either room.
Question: What protective coating could I apply to prevent the oak from turning darker over time? Don't want shiny, would like to stay as matte as possible.
Thank you, Ivan Vegvary

A finish may not prevent darkening.

Apply a floor finish. Burnish any gloss/high gloss finish with brown paper bag, ScotchBrite pad, burlap, or saw dust..... sometimes denim works well, also. When need refinishing, clean, sand lightly, apply new coat(s) and burnish, again.

Sonny