A harmonised adamantite rock is a special rock that can appear in the Trahaearn Clan district's mining area in Prifddinas while the Voice of Seren is active for the clan.
The rocks will last until they collapse, however more can appear. The mining experience is the same as the regular rocks; however, because they can only appear with the Voice of Seren active, there will always be an experience boost active when they appear.
There are four adamantite ore rocks that can harmonise out of the eight rocks that are there. All four rocks are able to harmonise at a time, although a very rare occurrence. Multiple players may mine from the harmonised rocks and receive adamantite ore.
Adamantite rocks cannot harmonise if the ore has already been mined.