This paper presents the integrated study of a distinctive bleach-decorated (bleached or etched) carnelian bead (S3074) discovered at the South Arabian port of Sumhuram (Dhofar, Sultanate of Oman), a Hadrami trading outpost active within regional and transoceanic trade networks between 100 BCE and 400 CE. Originating from a technology developed in the Greater Indus Valley during the 3rd millennium BCE, bleached carnelian beads remained markers of long-distance trade in the Early Historic and Medieval periods. Stylistic comparisons and SEM-based drilling diagnostics revealed that the Sumhuram specimen, the first securely identified example of this bead type in South-western Arabia, is consistent with production in north-western India. Its discovery in an urban context rather than a funerary assemblage raises interpretive questions about its circulation and meaning. While it may reflect structured trade flows linking Gujarat with South-eastern Arabia, the possibility that it was the personal possession of a South Asian individual temporarily residing in Sumhuram is equally plausible. This case ultimately exemplifies the entanglement of material culture, mobility, and identity in a cosmopolitan port city. Beyond economic exchange, the bead provides insight into personal histories and cross-cultural interactions across the Western Indian Ocean during the Late Iron Age. • First bleach-decorated carnelian bead identified in South-western Arabia. • Found at Sumhuram, a Hadrami port in Dhofar active in Indian Ocean trade. • Stylistic and SEM analysis indicates north-western Indian origin. • The find may represent structured trade or personal loss by a South Asian resident. • The case reflects mobility, identity, and cultural entanglement in the Western Indian Ocean.

The “Seima-Turbino trans-cultural phenomenon” is defined by the widespread adoption of socketed implements, such as axes (celts) and spearheads, often accompanied by knives or daggers, by Bronze Age communities across Eurasia. Most scholars agree that, originating in southern Western Siberia around 2200 BCE, this weapon- and tool-making tradition spread relatively quickly westwards, reaching Eastern Europe, and has been selectively adopted as far southeast as the Yellow River basin in China through several contact events, —around 1700 and, apparently, after a gap, —around 1300 BCE. Based on an analysis of weapons and tools from Zhengzhou, the early capital of the Shang dynasty (ca. 1600–1046 BCE), and Panlongcheng, a walled city in the middle Yangzi valley, flourishing around 1600–1230 BCE, I argue that Seima-Turbino had impact on Zhengzhou and, even more, on Panlongcheng, reaching it by 1400 BCE. Integrating typological analysis with geographical data and relative chronology, I propose that while the technology for making socketed celts may have arrived to Panlongcheng via Zhengzhou, the impetuses for spears, pikes, daggers, and knives likely came from northern and northwestern regions of China, where Seima-Turbino weapons and tools were longer known, channeled by contemporaneous Siwa and Lijiaya culture groups and by Shang affiliates, such as Laoniupo, across the Qinling Mountains through the Western Han River valley and Shangluo Corridor. Panlongcheng itself probably mediated some technologies and styles down the Yangzi valley to Wucheng. Although technological transfers not necessarily involve physical movement of people, the association of Seima-Turbino-style artefacts with cremation burials or cenotaphs at Panlongcheng reflects northern cultural traditions and may suggest presence of non-local individuals. This study underscores the Middle Yangzi region's participation in transregional Eurasian networks during the third quarter of the 2nd millennium BCE and challenges the dualistic view of Panlongcheng as a Shang “colony,” composed of Shang elites and controlled indigenes, revealing a more complex cultural and sociopolitical landscape. Lastly, it offers new references for the correlative dating of Seima-Turbino's southward spread. • Bronze weapons and tools at Panlongcheng and Wucheng mark the Yangzi valley as the southeastern extent of the Seima–Turbino tradition. • Northern-style weapons in cremation graves or cenotaphs indicate the spread of nonlocal mortuary customs and the presence of migrants. • Communities in present-day Gansu and on the Shaan-Shan Plateau likely mediated the transmission of northern cultural practices to the south. • Northern cultural elements at Panlongcheng signal high social complexity and challenge its reduction to a Shang colony.