Identification of the proto-inkstone by organic residue analysis: a case study from the Changle Cemetery in China

Heritage Science

Table 1 Peak assignments related to the chromatograms in Fig. 4 and the description of the compounds identified in the archaeological residue samples

Sample	Peak	Retention time/min	Composition	Main m/z values^a	Compound
Sample I	S1	20.67	C₁₄H₁₀	76, 89, 152, 178	Phenanthrene
	S2	28.45	C₁₆H₁₀	101, 202	Fluoranthene
	C_16:0	28.58	C₁₆H₃₂O₂	73, 117, 313^b	Palmitic acid
	S3	29.91	C₁₆H₁₀	101, 202	Pyrene
	C_18:0	34.17	C₁₈H₃₆O₂	73, 117, 341^b	Stearic acid
	S4	38.64	C₁₈H₁₂	114, 228	Benz[a]anthracene
	S5	47.55	C₂₀H₁₂	126, 252	Benzo[k]fluoranthene
	Sito	59.36	C₂₉H₅₀O	73, 129, 357, 396^b	β-Sitosterol
Sample II	S1	20.67	C₁₄H₁₀	76, 89, 152, 178	Phenanthrene
	C_14:0	22.81	C₁₄H₂₈O₂	73, 117, 285^b	Tetradecanoic acid
	S2	28.48	C₁₆H₁₀	101, 122, 202	Fluoranthene
	C_16:0	28.57	C₁₆H₃₂O₂	73, 117, 313^b	Palmitic acid
	S3	29.90	C₁₆H₁₀	101, 174, 202	Pyrene
	Ret	32.93	C₁₈H₁₈	189, 204, 219, 234	Retene
	C_18:0	34.17	C₁₈H₃₆O₂	73, 117, 341^b	Stearic acid
	PMA	35.61	C₂₀H₃₀O₂	73, 121, 257, 359^b	Pimaric acid
	DHA	37.88	C₂₀H₂₈O₂	73, 239, 357, 372^b	Dehydroabietic acid
	S4	38.91	C₁₈H₁₂	114, 228	Benz[a]anthracene
	S4	39.17	C₁₈H₁₂	114, 228	Triphenylene
	S5	46.52	C₂₀H₁₂	126, 252	Benzo[a]pyrene
	S5	47.54	C₂₀H₁₂	126, 252	Benzo[k]fluoranthene
	S5	48.19	C₂₀H₁₂	126, 252	Benzo[k]fluoranthene
	S5	49.03	C₂₀H₁₂	126, 252	Benzo[b]fluoranthene
	S6	55.39	C₂₂H₁₂	138, 276	Indeno[1.2.3-cd]pyrene
	S6	56.45	C₂₂H₁₂	138, 276	Benzo[ghi]peryene
	Sito	59.38	C₂₉H₅₀O	73, 129, 357, 396^b	β-Sitosterol