The Star Sapphire Crystal is a sapphire coloured crystal originating from the planet Zamaron that possesses parasitic abilities.
The original crystal was found by the immortal Zamarons within the planet's caves between a pair of mummified bodies of Khu-Fu and Chya-ra. Concluding that the gem was the ultimate expression of love the Zamarons sought to emulate it but failed to fully realize that the Sapphire was a parasite which suppressed its host's inhibitions.
Splitting the crystal into five gems, the Zamarons took to bestowing the crystal, upon various women in the universe to act as their representative "queens" known as "Star Sapphires". One of the first humans to be chosen as a "Star Sapphire" was Carol Ferris, who felt attracted to the residential Green Lantern, Hal Jordan, but was forced to aggressively attack him due to the gem's influence. As Jordan continually managed to defeat their "queen", the Zamarons eventually forced him to choose which would be the Sapphire's new host: Carol Ferris or his then-current girlfriend; Jillian Pearlman. Instead, Hal kissed one of the Zamarons, which the Sapphire immediately bonded to in the assumption that that was who he had chosen.
Realizing that the crystal was too unstable to be controlled on its own, the Zamarons attempted to lessen its power by reforming the five gems into a single crystal and installing it into a Power Battery to form their own corps in preparation for the coming War of the Light.
- In a bid to quell the rising war between the Green, Sinestro, Blue, Orange and Red Lantern Corps, the Star Sapphire Corps enters the Downtown Metropolis Battlezone and unleashes their crystals to convert the warring corpsmen to love.
- As part of the Valentine's Day Event, players can acquire various types of Star Sapphire crystals to place in their Lairs and Hideouts or League Halls.
- In the Valentine's Day Event, Green Lantern (Hal Jordan) recruits New Heroes to stop Mister Freeze, who has acquired Star Sapphire crystals in an attempt to use their power to bring about the resurrection of his wife. The New Heroes must stop him before he unleashes the energy of the crystals and destroys the city.
- In the Valentine's Day Event, Mister Freeze recruits New Villains to acquire Star Sapphire crystals in an attempt to use their power to bring about the resurrection of his wife.
- When an individual is in contact or encased within the crystal, it is capable of altering a person's emotional state over time. The Star Sapphire Corps use this ability to capture and convert members from other lantern corps into their own.
- The Star Sapphire Power Rings possess the ability to crystallize objects; to "preserve the ones the wielder loves". The power is great enough to crystallize an entire planet; as was the fate that befell the planet Xanador after a ring was sent to Dela Pharon; the lover of the planet's resident Green Lantern Corpsman. Her love was so great that, after mating with her lover, her power overflowed and killed her love before encasing the planet in sapphire crystal.