Types of lime binders in mortars used for the construction of the Ming Great Wall of China and their importance for the development of a conservation strategy

Built Heritage

Table 2 Water-soluble salts from Shanhaiguan/Hebei and Badaling/Beijing (wt.%)

Location	Sample	Na⁺	NH₄⁺	K⁺	Ca²⁺	Mg²⁺	F⁻	Cl⁻	NO₃⁻	SO₄²⁻
Hebei, Shanhaiguan/September 2019	H-SHG-Y01	NN	0.33	0.43	1.00	12.65	NN	3.65	NN	59.65
Hebei, Shanhaiguan/September 2019	H-SHG-Y02	0.19	0.09	0.42	1.64	6.76	≤0.01	7.75	0.30	30.42
Beijing, Badalin/October 2020	BDL-03	0.14	–	–	0.31	0.9	–	0.18	0.46	6.84
Beijing, Badalin/October 2020	BDL-04	0.02	–	–	0.02	0.31	–	0.12	0.17	1.41