Found this old button in with other vintage clothing buttons. The back side has Rich Orange Colour stamped on back with a vine/leaf pattern surrounding button post. The front has an naval type and crown on top.
Accordong to the "Buttons of the UK's Royal Navy" website: Diana's Buttons - Reference - British Navy Buttons
your button is a British Navy Lieutenant and Midshipman's uniform button, dating from only the thirteen years between 1812 to 1825.
British Royal Navy Officers buttons did not have a crown above the anchor until 1812.
Having the Royal Navy emblem inside an upright oval ended in 1825.
Thus, your button can only be from 1812-25.