Sanguinare

The Sanguinare, also known as the Blood Stone was a gemstone. This ended up in the hands of Kraxnor the Sycorax who used it to power the Sacrifice Engine. This was to harvest the souls of four planets to open a rift in the universe that'll expel the dark energy threatening it. The Twelfth Doctor with Grant Gordon, Lucy Fletcher and Jennifer Fletcher put a stop to the plan by removing the Sanguinare, causing the Engine to detonate, destroying the Sycorax spaceship.

They took the Sanguinare too the Nether Gate of Tersimmon and safely opened a rift using the powers of all the other gemstones, saving the universe from the dark energy safely. (COMIC: Ghost Stories)