Cahokia-Moundville Interaction

A 1997 chapter by the author concluded that evidence of direct interaction between Cahokia and the large Mississippian center at Moundville, Alabama, was negligible. This chapter updates that assessment, especially in light of much recent research on the earliest period at Moundville. Exotic artifacts include infrequent Mill Creek chert bifaces and hoe chips, a Missouri flint clay effigy pipe, and sheet copper objects with possible Cahokia connections. Mound architecture includes a “greathouse” arguably built in a Cahokian style. Even so, evidence of direct contact between the two centers remains minimal, and there is no evidence of Cahokian involvement in Moundville’s emergence.

Interactions between the Caddo and Cahokia Regions

Direct material evidence of contact between the southern Caddo area and Cahokia is sparse but of considerable interest because establishment of connections between the regions appears to have had profound implications for the subsequent history of the Caddo Area. Flint clay figures and a broad range of copper items including cut sheet copper hand symbols and long-nose god maskettes likely were brought to the Caddo area following visitations or pilgrimages to Cahokia during the 11th century. Movement of ritual items from Cahokia may have been accompanied by the transfer of ideas that modified Caddo religious practices, legitimized social divisions, and institutionalized positions of authority. The passage of people, information, and goods facilitated the establishment of new cultural traditions at local levels, and connected people in the Caddo area to the increasingly integrated “Mississippian” world in eastern North America.

Késő rézkori különleges temetkezések Balatonlelléről (Somogy megye)

Two Late Copper age inhumation burials were uncovered by istván Molnár in 2005 during the large-scale rescue excavations ahead of road construction in County So-mogy. in addition to the burial proper, both graves contained the skulls of additional individuals. in addition to the vessels, the 8–9-year-old child interred in Grave 415 had a bracelet of almost pure copper on his wrist, a black bead fashioned from jet or some similar organic material on his neck and a bead hammered from sheet copper. The burial mode and the jewellery items – currently unparalleled in the archaeological record – that were deposited in the grave clearly indicate that the child buried in the grave enjoyed a special status. The dna analyses revealed kinship ties between the boy and the other skulls placed in his burial.

Friction Stir Welding of Copper Alloy CuETP

Experimental researches that were performed in order to determine the mechanical parameters in the process of joining of materials using the FSW process are presented in this paper. The paper presents the joining of CuETP sheet copper alloy, with thickness of 5 mm, and provides details of the friction stir welding process. Besides that, the influence of tool geometry and the regime of welding on the quality of welded joints, was investigated. Experimental studies are made on the basis of the adopted multifactoral orthogonal plan, with varying of factors on two levels and repetition in the central point of the plan. Parameters varied in the experiment were: welding speed, rotation speed of tool, angle of pin slope, pin diameter and shoulder diameter. The family of tools is provided, based on the adopted geometric parameters. The experiment was carried out in a laboratory at ambient temperature in conditions similar to those in the production. In order to determine the quality of welded joints, mechanical tests were performed in the paper, and tensile strength and impact toughness were determined.

Copper Artifacts from Caddo Sites in the Southern Caddo Area

Copper artifacts have been found at only 18 Caddo sites in the southern Caddo area of Southwest Arkansas, Northwest Louisiana, southeastern Oklahoma, and East Texas. Most of these exotic copper artifacts are found in burial mound context in important civic-ceremonial centers, or in burials in non-mound cemeteries. About 80 percent of the known copper artifacts occur in contexts in sites that date to the Early Caddo period (ca. A.D. 1000-1200). These copper items likely are linked to the Cahokia exchange system, and represent prestige goods with ritual status acquired and displayed by leaders in different Caddo communities. By Late Caddo period times (ca. A.D. 1400-1680), copper items tend to be ear spools, especially copper-covered stone ear spools. Copper continued to be used as personal ornaments linked to specific Caddo individuals, but they no longer served for objects that may have been involved in public ritual, as there are no effigies, sheet copper hand cutouts, or maskettes from Late Caddo contexts as there were in Early or Middle Caddo period contexts.

Soldering sheets using soft solders

The paper contains strength tests results of joints soldered using lead and leadless soft solders. For tests lead solders types Pb60Sn40 and Sn60Pb40 and leadless soft solders types Sn95.5Ag3.8Cu0.7 and Sn96Ag4 were used. As basic materials steel sheet, zinc-coated steel sheet, copper sheet and brass sheet 100 x 20 x 1 mm was the test samples size. Always two sheets were cleaned and jointed together. For heating the propane-butane + air flame was used. Then the tested assemblies were loaded using the universal tensile-strength testing machine till to failure. At the tests the force needed for assemblies failure and failure type (in soldered joint, in basic material) were recorded. From measured data the solder strength was calculated. From the experiment results it follows that from the point of view of the soldered joints strength as well of the solder strength relatively small differences were found. At the same time it is evident that the joint strength and solder strength depend on soldered material type and on soldered joint lapping length. On the basis of carried out experiments it can be stated that the substitution of lead solders by leadless solders is possible without risk of soldered joints strength decrease.