NEW DATA AND A REVISED STRUCTURAL MODEL FOR FERRIHYDRITE: REPLY

and the interest they have shown in our paper (Eggleton and Fitzpatrick, 1988) and more particularly for prompting further examination of the ferrihydrite structure. Some of the points raised by Manceau et al. (1990) are welcomed in that they provide us with the opportunity to clarify and further emphasize the im-portant features of our original communication. We do not, however, agree with all their remarks. In their concluding remarks they state: " It is only by using adequate analytical tools (e.g., extended X-ray absorp-tion fine-structure spectroscopy and X-ray absorption near-edge spectroscopy), that the local order, the only preserved structural scale of poorly ordered com-pounds, will be elucidated. " We agree that adequate analytical tools should be used and for this reason w