Yes - the rock is definitely dolerite.
Though I can understand that some would consider the smooth hard rock faces as "granite".
It is a jumble of collapsed dolerite columns - with the cliff wall at the back being the same impressive columns that make up the entire mountain top.
This is a view down onto the Lost World from one of the lookout points near the top of Mt Wellington.
You can see the columns of the cliff wall with the rock jumble below.
- View to Lost World
The article suggests there is a least one place which is easy to enter (no ropes) and go a little way in.
I don't know where that is, perhaps someone else has more details on the area?
- but one could spend a lot of time enjoyably exploring around the rock jumble.
eggs