A band at about 835 nm pointed to the presence of Fe2+, whereas the peak at about 371 nm demonstrated Fe3+ (compare Wood and Nassau, 1968; Schmetzer et al., 1974; Platonov et al., 1978).
A band atabout 835 nm pointed to the presence of Fe2+, whereasthe peak at about 371 nm demonstrated Fe3+ (compareWood and Nassau, 1968; Schmetzer et al., 1974;Platonov et al., 1978).