Petrographic and geochemical analyses to characterise the source of built historical natural stones — a case study of the volcanic stones from historical quarries and Baoguosi Temple in the city of Ningbo, China

Built Heritage

Table 2 Major elements content of selected samples

Elements	M201809-1 (wt. %)	M201809-2 (wt. %)	M201809-3 (wt. %)	BGS (wt. %)	X201809-1 (wt. %)	D201809-2 (wt. %)	D201809-3 (wt. %)
SiO₂	65.80	62.74	62.33	66.09	70.22	70.58	73.02
TiO₂	0.55	0.62	0.71	0.51	0.39	0.33	0.20
Al₂O₃	14.82	14.86	14.56	14.71	12.95	14.03	12.83
Fe₂O₃	4.08	4.60	5.48	3.44	2.98	2.57	1.7
MnO	0.11	0.13	0.17	0.09	0.12	0.16	0.08
MgO	1.75	2.22	2.36	1.27	0.79	0.74	0.27
CaO	1.62	2.96	2.59	3.18	2.23	1.45	1.7
Na₂O	5.83	5.46	3.75	4.72	2.95	4.47	5.03
K₂O	2.77	2.70	3.89	2.56	4.18	3.82	3.28
P₂O₅	0.15	0.17	0.19	0.11	0.10	0.09	0.04
LOI	2.22	3.51	3.69	3.16	2.74	1.67	1.58
Total	99.71	99.97	99.71	99.85	99.64	99.85	99.74