King's Drop

The King's Drop is a perfect ruby gemstone stored in the Thaylen Gemstone Reserve on Roshar. It plays a key role in the Battle of Thaylen Field.
== Characteristics ==
The ruby is the size of a child's head and when infused glows with a blood-red light as bright as daylight. Although it is no larger than a gemheart from a greatshell, it is able to store Stormlight indefinitely; a normal gem of its size would run out of Stormlight in about a month. Perfect gems maintain their ability to store Stormlight indefinitely even if they are brought to Shadesmar. Scholars believe that the perfection of the crystal lattice is the reason for these unique properties.
The King's Drop is rumored to be a piece of the Stone of Ten Dawns, a legendary perfect gemstone.
== History ==
=== Storage ===
At the end of the Era of Solitude, the King's Drop was in the custody of the Thaylen Gemstone Reserve. It had stayed locked inside a closet-sized personal vault within the main vault of the reserve for over 200 years.
=== Attempted theft ===
After severely injuring herself in the Reshi Isles, Rysn took a job keeping ledgers for Queen Fen with an office in the Gemstone Reserve of Thaylenah. She was surprised when her former master, Vstim, visited the Reserve for an audit. Vstim and Rysn opened the vault with the King's Drop and regarded it with awe. Suddenly, an assassin disguised as a guard killed Tlik, attacked Vstim, and fought off multiple guards in an attempt to steal the gem. Rysn noticed that the assassin displayed unusual healing and illusory powers.
During the scuffle, Rysn's pet larkin, Chiri-Chiri, consumed the Stormlight from the ruby. The assassin was prevented from escaping when Chiri-Chiri drained what appeared to be Voidlight from his body, preventing the use of his powers and enabling Rysn to kill him with a crossbow. Rysn took the now-dun ruby and tried to determine how she could retrieve the wounded Vstim and exit the vault. 
=== Battle of Thaylen Field ===
When Odium's forces attacked Thaylen City, a thunderclast destroyed the Reserve as it searched for the ruby with several Fused. Although Rysn had already managed to flee with Vstim, Dalinar saw two more Fused locate their palanquin and steal the ruby. Dalinar realized that the gem must be special, and tasked Lift with retrieving it; Szeth soon came to help her. After some back-and-forth with the Fused, the duo were able to procure the ruby and Lift delivered it to Dalinar.
Dalinar was able to "lure" and trap Nergaoul, the Unmade responsible for the Thrill, using the gemstone. The ruby appeared to glow with Voidlight after Nergaoul was imprisoned. After the battle, Dalinar gave the gem to Navani for study. She remarked on the visual similarity to Gavilar's black spheres.
The gemstone was afterwards secured inside an aluminum box, which was then sunk to the bottom of the ocean, to prevent the Unmade from being released again.
== Trivia ==
* A ruby nicknamed Honor's Drop is mentioned in the Urithiru gem archive as one of the perfect gems guarded by the Order of Elsecallers of the Knights Radiant, presumably during the Heraldic Epochs. It has been speculated that the King's Drop is the same ruby in the present day.
== Notes ==