We report the Raman study on 6H-SiC to ultrahigh pressure of 95 GPa in a diamond anvil cell. The LO(Γ) and TO(Γ) Raman frequencies increase with increasing pressures. A very interesting turnaround in the LO-TO splitting is observed above 60 GPa. The density variation of the mode Grüneisen parameters for 6H-SiC is compared to that of silicon, cubic boron nitride, and diamond. The SiC is transparent to the visible light at 95 GPa and the anticipated metallic phase was not observed. © 1994 The American Physical Society.