hmm was a new thread rly necessary? lol should b merged with
http://forum.us.runesofmagic.com/showthread.php?t=41422
If I remember correctly this was the quest associated with a prior quest from Sheebo Kanten that gives u that weird "Explosive" item that doesn't disappear from ur bag after killing the Ape King the first time. After killing the Ape King, the pillar behind it generates the gem for that previous quest, in that quest when right clicking on the gem itself activates another quest, (after looking thru Runedatabase.com, I think it's the "Mysterious Gem" quest that gets activated, not sure tho, then the item in question is called "Special Jewel"), that sends you to Banki Lofit (51.6, 79.7). Unless I'm confusing this with another quest, after speaking with Banki, the quest icon ! doesn't show up on the npc's head, so most ppl think the quest ends there. But if u talk to Banki again, then the gem is released back to you along with another quest to give the jewel/gem to Sheebo.
Where you are in ur quest chain, I think Banki Lofit STILL has ur jewel/gem thats why Sheebo Kanten doesn't know anything because u nvr finished the previous quest in that area. Talk to Banki to get the jewel/gem again which is now called, then give it to Sheebo Kanten, then take the now-changed-&-called "Special Gem" from Sheebo Kanten to give it to
Sheelo Lance.