You don't often see real ivory added to jewelry anymore.  I acquired some old piano keys that had ivory on them.  After carefully cutting the ivory from the wooden keys, I decided that a pendant was the way to go to protect the delicate ivory and create a lovely piece of jewelry.  
I carved out a rectangle for the peridot setting and added a blue topaz as a complimentary color.  
 
The chain is sterling silver and is 18" long but can be made any length you need.  Please contact me with you request.