The Jowett anvil. Thanks to Mike Graham for this photo and The Old Texas Barbell Company in Lockhart, TX.
The anvil weighs 168lbs.
THIS IS NOT the anvil shown in the famous photos of Jowett lifting an anvil which in fact is a much smaller anvil, and has a different horn shape.
The anvil shown here does in fact weigh 168 lbs, and presents a one hand deadlift challenge. A one hand clean with a 168 lb anvil has never in fact happened.