Physicochemical investigation of prehistoric rock art pigments in Tewet Cave, Sangkulirang-Mangkalihat Site, East Kalimantan-Indonesia

Geotourism Hazards and Carrying Capacity in Geosites of Sangkulirang-Mangkalihat Karst, Indonesia

“…Owing to the possession of 240 pieces of rock art distributed over the entire roof of the cave, radiocarbon dating indicates that rock art in the Tewet cave in Sangkulirang-Mangkalihat karst is 40,000 BP (40 ka). It is considerably older than the Lascaux cave (35,400 BP) and the Chauvet cave (32,000) in France [48] and the karst area was presumed as the initial location for Austronesian humans to enter [49,50]. Furthermore, the maximum date for the earliest cave painting phase in the Sangkulirang-Mangkalihat Peninsula is 51.8 ka [26], and this also indicates the oldest cave paintings made by prehistoric modern human.…”

“…The Sangkulirang-Mangkalihat karst features hilly terrain, steep cliffs, and underground caves. The caves in this area have unique features, such as cave paintings (rock art) and different types of animal images that have archaeological significance [48]. Owing to the possession of 240 pieces of rock art distributed over the entire roof of the cave, radiocarbon dating indicates that rock art in the Tewet cave in Sangkulirang-Mangkalihat karst is 40,000 BP (40 ka).…”

Thermally-induced color transformation of hematite: insight into the prehistoric natural pigment preparation

“…This phenomenon can be occurred either naturally and/or synthetically (Faivre, 2016). Previous research's hypotheses stated that purple hematite on prehistoric rock art is formed due to the heat treatment of red hematite, thus changing the size and structural properties, albeit the hypothesis has not been proven (Ilmi et al, 2020;Nurdini et al, 2020). Meanwhile, research on natural pigments purple (Caput mortuum) by Castagnotto et al (2021) explained that natural pigment (hematite purity < 80%) cannot change then produce a purple color, and only pure hematite can obtain purple color due to heat treatment.…”

“…Ochre contained clay and silica with various types of iron minerals. These types of iron minerals in ochres produce a range of colors, from yellow, α-FeOOH—goethite ( Longa-Avello et al., 2017 ; Mondragón et al., 2019 ; Salomon et al., 2012 ), brown, -Fe 2 O 3 —maghemite ( Cornell and Schwertmann, 2003 ), red, α-Fe 2 O 3 —hematite, and purple, α-Fe 2 O 3 —hematite or KFe 3 (SO 4 ) 2 (OH) 6 —jarosite ( Hunt et al., 2016 ; Huntley et al., 2015 ; Ilmi et al., 2020 ; Kurniawan et al., 2019 ; Nurdini et al., 2020 ). In addition, other colors in rock art images, such as black, contain manganese oxide or charcoal ( McPeak et al., 2013 ; Chalmin et al., 2003 , 2004 , 2006 ), while white contains Al 2 O 3 2SiO 2 ·2H 2 O—kaolinite, Mg 3 Ca(CO 3 ) 4 —huntite ( Huntley et al., 2014 ), CaSO 4 .2H 2 O—gypsum or CaCO 3 —calcite ( Ilmi et al., 2021a ).…”

“…This rock art is currently the oldest found artwork depicting hunting activities in the world ( Ilmi et al., 2021b ). In addition, Studies on prehistoric rock art exhibit the purple color of hematite alongside the red color in several sites, such as in Australia and Indonesia ( Huntley et al., 2015 ; Hunt et al., 2016 ; Kurniawan et al., 2019 ; Ilmi et al., 2020 ; Nurdini et al., 2020 ). Previous studies stated that elements composition and particle size are different between purple and red hematite ( Cornell and Schwertmann, 2003 ; Marshall et al., 2005 ; Opuchovic and Kareiva, 2015 ).…”