Thermoluminescence dating of brazilian indigenous ceramics
Thermoluminescence dating of brazilian indigenous ceramics - Free no sign up naughty one on one chat
Two indigenous ceramics fragments, one from Lagoa Queimada (LQ) and another from Barra dos Negros (BN), both sites located on Bahia state (Brazil), were dated by termoluminescence (TL) method.
Tempers are non-plastic materials added to clay to prevent shrinkage and cracking during drying and firing of vessels made from the clay.
Negative painting is a technique employed by precontact Mississippian potters in the Eastern Woodlands, Mayan potters in Mesoamerica, and others, which involves covering the ceramic piece in beeswax or another resist, incised a design in the resist, then soaking the piece with a slip.
In the firing process the resists melts away, leaving the colored design.
The estimated ages were ∼1375 and 709 y for BN and LQ ceramics, respectively.
The ages agreed with the archaeologists' estimation for the Aratu and Tupi tradition periods, respectively.
The TL fraction was chemically treated, divided in sub samples and irradiated with several doses.
The plot extrapolation from TL intensities as function of radiation dose enabled the determination of the accumulated dose (D) obtained were 2.86 and 2.26 m Gy/year.They also used a hand-rotated turntable that allowed all sides of a ceramic piece to be painted with ease.These were first used in 500 BCE and continue to be used today.Carved wood or ceramic stamping paddles are used throughout the Southeastern Woodlands to create repeating designs.Clay can also be added to the main ceramic structure to build up designs.Hohokam potters and their descendents in the American Southwest employed the paddle-and-anvil technique, in which the interior clay wall of a pot was supported by an anvil, while the exterior was beaten with a paddle, smoothing the surface.