Trollsteinn

Trollsteinn is a block added by the Twilight Forest mod. This block, while it looks like an ore, does not smelt or drop any resources other than the block itself. It is a mostly decorative block, but the faces will change colour depending on how much sunlight is around it. If the face of the block has dark purple speckles and is emitting small purple particles, it means that hostile mobs are likely to spawn nearby. Trollsteinn does not detect light emitted from blocks such as Torches. It can only be found around the caves in the Highlands.