Cave goblin miners can be found in the Dorgeshuun mines under Lumbridge after completing the members-only Lost Tribe quest. Once attacked, a Cave goblin guard will attack you. These miners will mine the various iron and silver ores around the Dorgeshuun mines. Despite this they never actually occupy the ores, enabling players to mine any ores that they may choose. This means they are not a nuisance to players trying to mine iron or silver.
These Cave goblin miners are under the instruction of Mistag and mine the iron in order to use it to build and repair Dorgesh-Kaan. The goblins will also explain that they always build with bones as they have no access to trees. They also believe that Giant frogs (from which they get their bones for building) are fearsome to them.
They seem to use a pickaxe which looks like a cross-over between a Bone spear and a Scythe, though this "Bone pickaxe" does not exist in RuneScape. Also these are the only monsters which drop Mining helmet, one of the best light sources in the game.
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