A rock spire[1] is a column of rock in Metroid Prime.
The rock spire is not very strong, as a Charge Shot or Missile can destroy it. It is seen in two instances in the Magmoor Caverns only, although the invisible platform and Thardus are composed of similar rock. Both instances feature important power-ups.
In the first instance, Triclops Pit, a section of the column hides a Missile Expansion, which can be obtained when the X-Ray Visor is collected, although the spire can be shot down from afar. In the Lava Lake, the column at the lake's center contains the Artifact of Nature, the earliest obtainable Chozo Artifact. A few Missiles or a Super Missile is enough to destroy it.
References[]