What I found was from the server side and matches with many other valuable items which return a plausible drop chance

Hey, The database indicates that Garmoth's Heart has a drop rate of 6000. Other items show a drop rate of 1000000 which seems to translate back to 100%. By this logic, 6000 from 1000000 is 0.6%, making me believe Garmoth's Heart has a 0.6% drop chance. Using this method, Vell's Concentrated Magic ha...