We have recorded the extended x-ray-absorption fine structure (EXAFS) above the carbon K edge for diamond and highly oriented crystalline graphite using 250-800-eV synchrotron radiation. The spectra are used to test phase and amplitude transferability of the C-C EXAFS signal between the two bonding forms of carbon. We find excellent phaseshift transferability with errors in distances less than 0.01 AIS. Amplitude transferability is worse but better than 20%. Implications of our results for structural determinations of C-C bonds in molecules and solids are discussed. © 1988 The American Physical Society.