10.6084/m9.figshare.6024785.v1 Meng Ren Meng Ren Renfang Wang Renfang Wang Yimin Yang Yimin Yang MOESM2 of Identification of the proto-inkstone by organic residue analysis: a case study from the Changle Cemetery in China Springer Nature 2018 Chinese inkstone Shape Pine-soot ink Dehydroabietic acid 2018-03-23 05:00:00 Figure https://springernature.figshare.com/articles/figure/MOESM2_of_Identification_of_the_proto-inkstone_by_organic_residue_analysis_a_case_study_from_the_Changle_Cemetery_in_China/6024785 Additional file 2: Figure S2. The extraction solvent of chloroform/methanol (2:1 V/V) (a) and acetone (b) after centrifugation.