Since its discovery in 1987, the Early Bronze Kestel Mine has been a topic of archaeological and geological controversy. The initial interpretation of the extensive marble-hosted galleries as the oldest known tin mine was challenged due to the low tin grade in remaining hematite-quartz veins, and it was suggested that Kestel was more likely mined for gold. Mineralogical analysis of the remaining mineralization was compared to a heavy mineral concentrate extracted from the soil preserved within the mine. The compositionally complex, arsenate-rich mineral assemblage from the mine sediment, contrasts with that of the remaining surface mineralization. Thus, the outcropping veins do not represent the nature of the extracted ore. Only one grain of gold was found in the heavy mineral concentrate, whereas cassiterite composed 1.5% of the sample. Cassiterite occurs in complex assemblages with arsenates, clays, hematite, quartz, and dolomite, bearing resemblance to hematite-arsenate tin mineralization that occurs near Kayseri, 60 km to the northeast. These findings indicate that although gold was a trace component of the Kestel ore, cassiterite was the mineral of interest to the Early Bronze Age miners, and that Kestel represents the earliest evidence thus far for an emerging pattern of local tin exploitation.

Abstract An unexpected new source of tin was recently located at Hisarcık, in the foothills of the Mount Erciyes volcano in the Kayseri Plain, close to the Bronze Age town of Kültepe, ancient Kanesh and home to a colony of Assyrian traders. Volcanoes in Turkey have always been associated with obsidian sources but were not known to be a major source of heavy metals, much less tin. X-ray fluorescence analyses of the Hisarcık ores revealed the presence of minerals suitable for the production of complex copper alloys, and sufficient tin and arsenic content to produce tin-bronze. These findings revise our understanding of bronze production in Anatolia in the third millennium BC and demand a re-evaluation of Assyrian trade routes and the position of the Early Bronze Age societies of Anatolia within that network.

AbstractThe first occurrence of orbicular rocks in Turkey is reported. They are gabbros in a dyke in the Baskil island-arc magmatic suite, of the southern branch of the Alpine-Himalayan chain. The orbicules have lithologically varied cores, regular shells of troctolitic composition, with a radial arrangement of olivine and plagioclase crystals, and a matrix of vari-textured gabbro. Rock and mineral analyses indicate that magmatic crystallization began near the inner margin of the troctolitic shells. Metamorphic hydration of minerals in cores, shells and matrix followed directly after the later stages of magmatic crystallization, as part of a continuous process, and thus a magmatic-metamorphic origin for the orbicules is proposed. Alternative hypotheses for the development of the orbicules are discussed: one involving the development of a protocrystalline magma shell, the other rapid crystallization during upward migration of xenolith-bearing magma.

Summary In the Eastern Taurus, The Elazıǧ nappes shown an ophiolitic association overlain by andesites and intruded by calc-alkalic granites, both of Late Cretaceous age. The basin was compressed in the Late Cretaceous between two metamorphic massifs each with a sialic basement and platform-type Permian to Mesozoic cover. This history indicates Late Cretaceous subduction under the Taurides and subsequent compression of the basin and arc. Attempts to place this Tauric subduction in the geodynamic history of Turkey lead to conflicting interpretations and two alternative models are presented. The first involves a single Tethyan ocean subducting northwards below the Pontides and southwards below the Taurides. The latter led to the Late Cretaceous opening of back-arc basins which split the formerly continuous Tauric-Arabian platform. Southward subduction ended when the ridge reached the trench, leading to compression of the Elazıǧ back-arc basin, southward obduction and closure of the ocean. The residual, Upper Cretaceous marginal basin controlled the subsequent Tertiary development of the area. The second model involves a northern Tethyan ocean and a southern Mesogean ocean, both subducting northwards. Subduction of the southern ocean generated calc-alkaline magmatism and deformation of the leading edge of the Tauric blocks. The Elazıǧ basin closed as a result, having earlier formed either as a subduction-related marginal basin or as a pre-existing extensional basin. Southward obduction took place from both oceans. After closure of the Tethyan ocean, Tertiary development was controlled by reactivation of Mesogean subduction.