Need Adventure Idea

Not sure if I have the right board but I'll ask anyway....

I am running a quick AD&D 3e adventure tomorrow evening. I plan to drop the characters into Mirkwood. They are being chased by Goblins through the woods and find a cave that looks suitable to hide in. A dying elf is in that cave, having barely survived his venutre into the dungeon below the cave. I have a quick dungeon set for them where they retrieve a red gem shaped like a fist. I need an idea of what and why that gem exists and why the elf may have wanted it. My Middle Earth knowledge is limited to the Hobbit (for now - I am reading Tolkien daily now to learn more). So I would appreciate any help you might provide.

Thanks in advance.

I'd like to help, and I got a couple ideas. If you could
write back and tell me who your characters are and what races, I'll modify and give them to you.

A mix of races. I have 2 elves (Ranger and Cleric), a dwarf (sorcerer), one human (monk) and a halfling (thief). They happen to be wandering through Mirkwood and happen upon this cave while being chased. They duck in and the adventure starts...

Thanks for the help...

a dwarf sorcerer didn't seam like a very good idea for me

i'm sorry but i never see in any game a dwarf who could wield magic

have few idea i'll get back to you when i have more time

True enough, the religion of the Dwarves is cloaked in secret! If there ever were such a thing as a dwarf mage, then he would be out in the open for a very serious purpose indeed!

The gem was stolen long ago from the hilt of the Sword of Durin! If it is recovered, a great reward and the unending thanks of all dwarves would belong to those who retrieved this treasure!

If the guy whew wanted it has magic, why not have the gem magic? That would be a good reason for him to want it.