Table 2.

A comparison of the mineral contents based on the XPS data performed on the fracture surfaces of young (48-year-old) and old (78-year-old) bone.

48-year-old female
Location	C	O	Si	Na	Zn	N	Ca	P	Mg	Cl	P/Ca
1	80.9	13.6	2.4	1.2	0.9	0.5	0.4	0.1	0	0	4.00
2	80.3	13.4	1.6	1.3	1.0	1.6	0.2	0.1	0.3	0.2	2.00
3	82.1	13.7	1.1	1.2	0.9	0.6	0.4	0.1	0	0	4.00
4	77.8	15.6	1.7	0.4	1.0	2.2	0.3	0.6	0.3	0.1	0.50
5	80.8	13.7	3.5	0.4	0.5	0	0.7	0.1	0.3	0	7.00
6	79.9	14.2	2.0	0.7	0.9	0.6	0.5	0.7	0.5	0	0.71
Average (S.D.)	80.3* (1.43)	14.03 (0.81)	2.05* (0.83)	0.87 (0.42)	0.87* (0.19)	0.92 (0.82)	0.42* (0.17)	0.28 (0.29)	0.23 (0.20)	0.05 (0.08)	3.04 (2.47)
78-year-old-female
Location	C	O	Si	Na	Zn	N	Ca	P	Mg	Cl	P/Ca
1	81.7	12.8	0	0	0	0.8	3.8	0.7	0	0.2	5.43
2	76.8	14.8	0.1	0.9	0.1	1.3	4.2	1.6	0.1	0.1	2.63
3	75.6	15.1	0.7	0.6	0	2.8	3.4	1.1	0.2	0.5	3.09
4	72.5	15.2	0.2	0.8	0	2.8	2.1	5.5	0	1.0	0.38
5	65.9	13.8	0.4	1.6	0	1.5	2.1	12.1	0.1	2.6	0.17
6	71.4	17.0	0.3	1.2	0	1.2	2.2	5.7	0.2	0.9	0.39
Average (S.D.)	73.98* (5.37)	14.78 (1.42)	0.28* (0.25)	0.85 (0.54)	0.02* (0.04)	1.73 (0.86)	2.97* (0.95)	4.45 (4.35)	0.10 (0.09)	0.88 (0.92)	2.01 (2.09)

^*This indicates a statistically significant difference (p < 0.05) between the means of the young and the old.