Hematite as unprecedented black rock art pigment in Jufri Cave, East Kalimantan, Indonesia: the microscopy, spectroscopy, and synchrotron X-ray-based investigation

Rock art and frontier conflict in Southeast Asia: Insights from direct radiocarbon ages for the large human figures of Gua Sireh, Sarawak

“…It is also clear that there are geological salts and other evaporites on the rock art surfaces and that a small amount of the limestone upon which the rock art is executed was incorporated during pigment sampling. Again, geological salts and other evaporites on the rock art surfaces are consistent with panel taphonomy in the region [ 4 , 8 , 42 ], and the relatively sparse build-up of geological salts (presumably gypsum) or other evaporates indicates remodelling of the limestone surfaces for hundreds or, at most, thousands of years.…”

“…Southeast Asia, after red, [9,[41][42][43]; with small anthropomorphic figures, often in active poses, dominating the rock art corpus [44].…”

“…Published recordings of similar black anthropomorphs with filled-in triangular torsos in central Island Southeast Asia include Gua Hagop Bilpo in Sabah [ 7 , 48 ], Gua Cincin in Kelantan [ 26 , 41 , 49 – 51 ], as well as at caves and rock shelters in Indonesia containing many hundreds of motifs including more than 30 sites in East Kalimantan (Indonesian Borneo), among them Tanjung Lokan, Kapusa Hulu and Batn Cap, Kayong [ 7 , 9 , 42 , 46 ], Liang Lumba in Central Kalimantan (Indonesian Borneo) [ 7 , 11 :166, 48 ], and numerous sites across the Maros-Pangkep and Bone regencies of southern Sulawesi [ 8 , 9 ]. There is considerable diversity in the graphic conventions of the black drawings of the region, particularly the anthropomorphs with more slender and elongated forms noted across central Island Southeast Asia and into Peninsular Malaysia [ 38 , 39 , 51 – 53 ], consistent with the Austronesian drawing style developing and changing over time as observed in the black pigment rock art of the Pacific [ 38 , 43 , 54 , 55 ].…”

“…Finally, in Borneo (East Kalimantan), black (along with red and purple) rock art paints at Jufri Cave have been argued to be a hematite mineral pigment [ 42 ], though we note that such a characterisation could equally come from the incorporation of the case-hardened Pleistocene cave surfaces of the region which contain ubiquitous iron minerals including hematite [ 3 , 8 ].…”

X-ray Synchrotron Radiation to Look at Pigments in Antiquities: Overview and Examples

“…SR-based methods have been proven to be particularly suitable for characterizing pigments in wall paintings and rock art [21], sometimes in combination with in situ investigations [22] and traditional laboratory-based analyses on microsamples [23,24]. In detail, chemical and mineralogical SR-based techniques (e.g., SR-µXRF, synchrotron radiation macro X-ray fluorescence (SR-MA-XRF), SR-µXANES; SR-µXRD) have been successfully employed in identifying minor phases and obtaining important crystallographic data separating anthropogenic markers and post-depositional processes [21] and to reveal the relationship between the physicochemical properties (e.g., crystallinity, morphology, surface density) and the color in iron-oxide-based decorations in caves [22][23][24][25] as well as to determine iron-oxide-based compounds present in small quantities that are quite difficult to detect with classical methods on intonaco [26]. The SR-µXRD technique has also been used to distinguish original from repainted rock art [21] and to identify the nature of pigments on prehistoric ceramic decorations [27], where the characterization of Fe-and Mn-based compounds is not straightforward and the use of advanced methods becomes fundamental [28].…”