P.S.1. More details are available in the help for the chests.
P.S.2. Some responsibility with this item is required, as the intention is not really to swamp the whole disc in buried treasure. Therefore, the sale is restricted to players who have one of the "Experienced Quester" or "The Happy Wanderer" achievements.
P.S.3. If you have a shovel and it doesn't work because the MUD hasn't rebooted since this post, you may need to SU with it first.