Riddle Me This - Can you solve it?

A riddle for my readers. Can you figure out what it is? Post answers in the comment section below! =D

The gateway is clear,

Though the facade black,

To agape unwated portals,

Convey them what they lack,

A key that holds one color,

Nests within this room,

Seize it before this enigma burns to ash,

Or repose within this tomb.

Author's Note

Extra Reviews for the winner!