The identification of Fe^(2+) in the M4 site of calcic amphiboles: reply

Experimental evidence indicates that absorption from Fe^(2+) in the M4 site dominates the optical spectrum of most calcic amphiboles in the 1000 nm region in the spectrum. Contributions from Fe^(2+) in M1, M2 and M3 occur in the 850-1150 nm region, but the intrinsic intensity of absorption by Fe^(2+) in these sites is much less than that of Fe^(2+) in M4