Densinium Ore

Densinium Ore is a tier 6 ore. It can be found on Cyber Spheres, Gas Giants and Shadow planets.

Note that this ore is very scarce near the surface. Underground layers of the planet will have significantly more of it.

It slightly glows in the dark, so you can notice it even without Ore Detector.

Unconventional uses
Densinium Ore increases hitpoints of the block by 62. If your base is suffering from damaging weather (such as Cosmic Blasts), you can use Material Mod Placer to add Densinium Ore to the blocks that need extra durability. Alternatives: 1) tile protection from Field Generator, 2) using already sturdy blocks like Diamond Block.