code/modules/mining/boulder_processing/boulder_types.dm 
| /obj/item/boulder/artifact | Boulders with special artificats that can give higher mining points |
|---|---|
| /obj/item/boulder/gulag_vent | Boulders spawned by the vent in the work camp, contain exclusively iron so we can have a reliable payout |
| /obj/item/boulder/gulag | Boulders usually spawned in lavaland labour camp area, broken open with pickaxe like a loot box |
| /obj/item/boulder/shabby | lowgrade boulder, Exists as an admin spawn for testing |