I know that vector resources are more my brother's field of work, but I did have my reasons for doing this (shortly to be revealed when I submit my next deviation ... which thankfully I have already made).
Oh, and if you don't already know, my brother is this fine fellow and here is a link to his most popular vector resource pack containing 10 very stylist guitars [link]

Downloading this will gain you the Vector Crystal.rar file. This includes the 6 following files:
Crystal LineArt.eps (basically a nine-sided shape, or nonagon as they are sometimes called, with all of the vertices connected)
Crystal LineArt.png
Crystal [with Lines].eps (this is the line art coloured in correspondence to an image of a ruby I used as reference)
Crystal [with Lines].png
Crystal.eps (this version no longer has lines as cause the image to lack realism)
Crystal.png

The line art contains 36 construction lines, plus the ruby's crown.
The ruby itself contains 154 facets
That's like 190 layers in total *faint*

Although all the downloadable files are based on a ruby, in the preview I have demonstrated that many other types of precious stone can be made simply by altering the hue in Photoshop

Enjoy people ... oh, and if you download it, please favourite it

I know the whole vector style makes it look a bit cartoony, so they're best viewed as thumbnails, MSN display pictures and avatars.
I also intend to use a graphics table to add tone on top of the crystal to make it look as realistic as possible for the final version.