Table 2.

Elemental compositions of the locally sourced materials.

	Elements composition	Locally sourced materials
		Detarium microcarpum	Brachystegia eurycoma	Rice husk
i.	Silica	N/A	N/A	N/A
ii.	Alumina	N/A	N/A	0.01–0.025b
iii.	Ferric	N/A	N/A	0.005b
iv.	Calcium	0.34–0.35a	0.72–0.80a	0.01–0.02b
v.	Magnesium	0.10–0.17a	0.16–0.21a	0.005–0.02b
vi.	Sodium	0.13–0.14a	0.05–0.11a	0.002–0.005b
vii.	Potassium	0.15–0.18a	0.21–0.24a	0.002b
viii.	Phosphorus	0.15–0.18a	0.30–0.33a	N/A

Sources: a. Uhegbu et al. (2009); b. Subbukrishna et al. (2007).