Abstract
It is shown that recently published experimental data from two independent sources on the pressure dependence of the Raman frequency of diamond support the idea that this frequency would make a good high-pressure calibrant. Equations published in a previous paper (Sherman, 1982) are shown to give more reliable predictions than those used in the two more recent papers (Hafland et al., 1985 and Goncharov et al., 1985), and some of the implications of this fact are considered.