In Brief Edit
Shattercrystal is the colloquial name for a crystalline substance which displays unusual properties when high-powered Ultraviolet-spectrum light is applied. The most commonly-used one is the release of vast amounts of energy, allowing it to be used not only as a powerful reactor for space-faring vessels, but also in the construction of Worm Gates, the method by which interstellar travel is possible in the life-span of the average spacefaring species.
Unfortunately, it tends to react explosively upon contact with any form of oxygen, producing even more high-powered Ultraviolet-spectrum light, and is thus subject to strict and boring codes of safe handling even among the most suicidal and callous of species.
Shattercrystal was discovered by the Soarine as a contaminant growing on the inside of particle accelerators. It's explosive properties and extreme energy production were discovered very shortly afterwards.
The primary use of shattercrystal is, as previously mentioned, as reactor cores for spacefaring vessels. Power levels are modulated by controlling the intensity of UV light emitters around the containment case. When controlled within specific limits, the crystal's energy is released as heat, the heat energy produced heats the substrate surrounding the crystal core, which then powers electrical turbines to provide power for whatever engine system the ships are outfitted with.