III. IDENTIFICATION - National Park Service- gold extraction stamp mills process ,Stamp Mills such as this one, located at the Reed Gold Mine in North Carolina, crushed gold ore into a sand-like consistency which was then washed across copper plates where mercury was …TREADWELL MINE - JuneauThis stamp mill’s successful extraction of gold from hard rock convinced John Treadwell that this process could be used here to make money. The next year this small mill was replaced by a larger mill with 120 stamps.