Here's my Diamond Shader ver. 01

It has some nice features :

1. No mental ray needed
2. Fast enough with raytracing (software render)
3. No HDRI, GI, AO & Photonics stuff

I use ramp for the chromatic abrev.
To use with MR, adjust the BM_Diamond_Chromatic_ramp1 color.

Just render it to see the chroma beauty of it :)

Note : sample included

Any suggestion and question to compoziting@yahoo.com