More than one hundred grains of SiC have been recovered from podiform chromitites in the Pozanti-Karsanti ophiolite in Turkey,which has been interpreted to have formed within an ancient subduction zone setting.These SiC crystals are transparent,usually occurring as irregular flakes or fragments,with sizes of50-300μm.They generally have different colours,including blue,light green to green,and colourless.Several metallic silicon(SiO)inclusions have been detected in the SiC.Laser Raman analyses show that the SiC crystals from the Pozanti-Karsanti chromitite are dominated by6H-SiC polytype,with subordinate3C,4H and15R polytypes.Carbon isotope analyses on the SiC have been determined using the CAMECA1280-HR Secondary Ion Mass Spectrometer(SIMS)at the GFZ,Potsdam.Thirty-two carbon isotope analyses on16SiC grains have been obtained.δ13CPDB values of SiC fall in a narrow range from-30.5to-27.2‰.The mean value and standard deviation of32analyses is-29.0±0.9‰.