Table 2 Semi-quantitative XRD phase composition (wt%) of AFB500 and AFB700 samples.

Phases of AFB500 sample

wt %

Fe₃BO₆

25

FeB₂O₄

24

AlBO₃

18

B₂O₃

33

Phases of AFB700 sample

wt %

Al₄B₂O₉

27

Fe_2.964O₄

6

FeB₂O₄

22

B₂O₃

45