It's looks like you're mostly there. I've got Enhance:C Organic 1 set on Dirt as the subshader of my color gradients and maybe kick down the shininess. I had it pretty low which gives a big highlight.

Unfortunately I didn't save that scene after I was done or I'd just post it.

Regards,

Eric Winemiller
Digital Carvers Guild
Carrara and LightWave plug-ins