It is not known to evolve into or from any other Pokémon.
Carbink is a gray Pokémon that resembles a rock covered in light-blue crystals such as an ore. A white, fluffy collar separates this Pokémon's limbless body and head. Carbink has blue eyes, a light-blue crystal on top of its head and big, flat rhomboid ears. It can fire energy beams from the crystal in its head.
Carbink is born from temperatures and pressure underground, and it has slept for millions of years since its birth. Some have been unearthed during cave excavations. Rarely, Carbink will undergo a strange mutation and transform into Diancie. In Alola, the main predator of Carbink is Sableye, which stalks Carbink due to its diet of gemstones. However, Gabite usually takes the Carbink before the Sableye can.
In the X & Y chapter, a group of Carbink lived in a cave near where Korrina, Gurkinn and Diantha camped as fugitives. A thief knocked out several of the Carbink inside the cave in order to steal the prized Diancie, but just as he made it out of the cave, he was stopped by the fugitive trio and eventually defeated by Diancie.
Carbink could be based on the carbuncle, a mythical fairy-like creature that was rumored to have gemstones growing out of it, and referring to its power to shoot rays or beams of light from the gem on its head. Its appearance is likely based on an ore, a type of rock that contains minerals with important elements which are valued for a high price.
Carbink may be a combination of carbuncle, carbon (element diamonds are composed of), carat, and tink (to tinkle).
Melecie may be a combination of melée (small cut diamonds), 珍しい mezurashii (rare), and 石 ishi (stone).