Strontium isotope evidence for a trade network between southeastern Arabia and India during Antiquity.

Cotton (Gossypium sp.), a plant of tropical and sub-tropical origin, appeared at several sites on the Arabian Peninsula at the end of the 1st mill. BCE-beginning of the 1st mill. CE. Its spread into this non-native, arid environment is emblematic of the trade dynamics that took place at this pivotal point in human history. Due to its geographical location, the Arabian Peninsula is connected to both the Indian and African trading spheres, making it complex to reconstruct the trans-continental trajectories of plant diffusion into and across Arabia in Antiquity. Key questions remain pertaining to: (1) provenance, i.e. are plant remains of local or imported origin and (2) the precise timing of cotton arrival and spread. The ancient site of Mleiha, located in modern-day United Arab Emirates, is a rare and significant case where rich archaeobotanical remains dating to the Late Pre-Islamic period (2nd-3rd c. CE), including cotton seeds and fabrics, have been preserved in a burned-down fortified building. To better understand the initial trade and/or production of cotton in this region, strontium isotopes of leached, charred cotton remains are used as a powerful tracer and the results indicate that the earliest cotton finds did not originate from the Oman Peninsula, but were more likely sourced from further afield, with the north-western coast of India being an isotopically compatible provenance. Identifying the presence of such imported cotton textiles and seeds in southeastern Arabia is significant as it is representative of the early diffusion of the crop in the region, later to be grown extensively in local oases.

Analysis of frankincense in archaeological samples by gas chromatography-mass spectrometry.

Four archaeological samples, unearthed from Qana in Yemen were analysed by analytical technique, currently applied in the field of petroleum geochemistry, and by gas chromatography coupled with a mass spectrometer (GC-MS). Sample no 1286 comes from a burned warehouse and samples no 964, 963 and 962 from the central sanctuary. These specimens were probably exposed to a heating source. In each case olibanum resin was identified according to the presence of their chemical markers corresponding to alpha- , beta-boswellic and lupeolic acids (3alpha-hydroxy-olean-12-en-24-oic, 3alpha-hydroxy-urs-12-en-24-oic and 3alpha-hydroxy-lup-20(29)en-24-oic acids) and their respective O-acetyled derivatives (3alpha- O-acetyl-olean-12-en-24-oic, 3alpha-O-acetyl-urs-12-en-24-oic and 3-O-acetyl-lup-20(29)-en-24-oic acids). Concerning the thermal degradation state of samples, the GC-MS results are in agreement with the geochemical ones. Sample no 1286 and 964 correspond to ageing incense which has not undergone any heating action and are consequently relatively well preserved. Lastly, samples no 963 and 962 are thermally degraded resins and their gross composition data permits to conclude that sample no 963 is only partially burnt while sample no 962 has been much more degraded.