I need to make a cost calculations for SiC and Cordierite ceramic parts.

I know how to calculate e.g zerodur parts, but not yet SiC.
So, I'm looking for machining parameters for SiC and Cordierite. I was hoping anybody would be able to help me with this.

What would help me as wel is if anybody would be able to tell me the machability of SiC and Cordierite compared to Zerodur. Someone told me SiC is 4 times tougher to machine than zerodur and Cordierite 2 times. Green machining of both would be factor 0.5.
I need confirmation of these factors.

I'm also looking for parameters to determine sintering times and/or HIP times for SiC and Cordierite.

Thank you in advance for any help.