Iolite sounds like a good choice.  Moldavite, to me, is more a heart chakra stone.  

BTW, I meditate in bed (I live in a 10x12 foot cabin), with a nice hunk of chevron amethyst at the head.

Moldavite is one stone that is linked with the Cosmic or Galactic energies and works with the following areas, interdimensional, exter-terrestrial and those of ancient energies and knowledge.
It works great the the third eye, the throat and crown chakra systems,
Now if you combine this stone with others that work with the third eye will help in meditation but the moldavite will connect with the higher consiouness while the other stone of your choosing helps with the meditation.
The moldavite is sort of like the enegizer bunny  to the other stone of choice.
Some Third Eye stones are: Iolite, Amethyst, Hawk's Eye, Sapphire and Tanzanite, just to name a few.
When dealing with moldavite the choice of color of the stone is just as important as the lighter green is more of connections while the darker the green the better is is used in healings as the dark green brings about the primal energies needed for healings.

Hope this help you

I just got a piece of this beauty yesterday and talk about a magical and energetic addition.  Love it!