Charcoal carbon dating
Even then, there remains an inbuilt age effect, albeit somewhat reduced.
A recent re-analysis of New Zealand's corpus of radiocarbon determinations from the Rafter Laboratory at the IGNS has suggested that problems associated with inbuilt age of wood had created spuriously old dates which needed to be culled with the help of a discard protocol.
The two differed by 260 years at the crucial Julian year of 1539, when one of the main Mayan cycles ended, and radiocarbon dating was used to try and solve which was correct.
Samples of Sapodilla wooden beams found spanning inscribed Late Classic Mayan doorways at Tikal were dated by the University of Pennsylvania, and it was found that the Spinden correlation was correct.
Shortly after the dates were released, Satterthwaite (1956; in Fedick and Taube, 1992) questioned their validity because the beams had been reduced in size and their exterior bore no resemblance to the original trees.
According to him, the dates were erroneous because they failed to date the event of the building of the temple.