The medieval period in the region near the Aral Sea must have been the era of significant sociopolitical changes and notable transitions in material culture. This prediction was tested with a metal assemblage consisting of numerous bronze and brass objects, mostly small items for personal use, excavated from the medieval (ca. 800–1000 AD) site near the Aral Sea in Kazakhstan. A technological transition driven by the growing reliance on brass was noted in the remarkable complexity in alloy recipes, in which recycled bronze and cementation brass served as the key materials along with elemental copper, tin, and lead. Different combinations of these materials were found to have resulted in the establishment of a dual technological tradition based on both bronze and brass. The notable transition and complexity as observed in the metal assemblage under consideration are interpreted as a reflection of the dynamic political settings in which both mobile pastoralist and sedentary farming groups were incorporated to form a dual social structure.

咸海附近地区的中世纪时期一定是重大的社会政治变革和物质文化显着转变的时代。这个预测是用由大量青铜和黄铜物体组成的金属组合物进行测试的，这些物体大部分是自哈萨克斯坦咸海附近的中世纪（大约公元800-1000年）遗址出土的个人用小物件。在合金配方中异常复杂的过程中注意到了对黄铜日益依赖的推动下的技术转型，其中回收的青铜和胶凝黄铜与元素铜，锡和铅一起成为关键材料。发现这些材料的不同组合导致建立了基于青铜和黄铜的双重技术传统。