Since the last great war when the Burning Legion was defeated, I have searched for sources of demonic corruption in orc society.  The collar you brought me confirms my fears.$B$BIt belongs to the Burning Blade, a cult that rallies around an item of demonic power.  It is called the Demon Seed, and it resides in the Barrens atop Dreadmist Peak.  It must be destroyed!$B$BGo to Far Watch Post, on the border of the Barrens to the west, and speak with my assistant, Ak'Zeloth.  He will direct you further.