The Pokémon is still known as Diancie outside of Japan, and as previously reported is a Rock and Fairy Type. It's known as the Jewel Pokémon and the official site also mentions that Diancie is a rare Pokémon whom is loosely related to Carbink. The full write-up is as follows:Pokémon said:"Diancie is an extremely rare Pokémon, created when Carbink undergoes a strange mutation. Its glittering pink body is said to be the most beautiful sight in the world.
Diancie can create diamonds out of thin air by compressing the carbon in the atmosphere with its hands. It uses these jewels in battle to attack enemies and protect itself"
No details have been given on how to obtain Diancie currently. Diancie brings the current number of officially revealed Pokémon up to an impressive 719.