Ancient Basalt

 can be found on the surface at the far right of the map. The Player is not able to place the block once it is taken.

Properties
It can not be broken by any mark of Miniaturizor and can only be broken by Explosives or monsters (as opposed to Basalt, which can be mined by Miniaturizor MK V).

Location
It can be found at the Volcano Mountain, Volcano Conduit and Great Cave

In-Game Description
Very strong and ancient basalt.