Carbon dating non organic materials
A variety of dating methods are available and, depending on the available information, materials and technology, scientists must decide which method will provide the most accurate results in each case.
For archaeology, determining time span and the ages of artifacts or sites is an incredibly important part of archaeology.
There are two very destructive steps in radiocarbon dating as it is now practiced.
( 1) Pre-cleaning to rid organic artifacts of the commonly occurring humic acid and carbonate/oxalate contaminants are accomplished by serial strong acid, strong base, and strong acid treatments.
Dendrochronology, or counting tree rings, is particularly useful for logs preserved in fairly recent sites and that can be compared to known historic trees.
There are several methods that scientists use including counting the annual cycles of sediment deposition, or varves, in glacial lakes, which allow archaeologists and geologists to determine the age of those lake deposits if they continued up to the present day.
Plasma oxidation may also be preferable for any type of sample containing significant amounts of oxalate-containing minerals.
Two previous studies, one from our laboratory  and one from the Oxford Accelerator mass spectrometry laboratory [1 0] found that in some circumstances, traditional acid treatment does not remove all of the contaminant calcium oxalate minerals.
Atmospheric nuclear weapon tests almost doubled the concentration of 14C in the Northern Hemisphere. [vi] How would a recent past of high volcanism, as shown by ancient lava fields, ash falls, and dead volcanoes, have affected ancient carbon isotope ratios?
Factor 4: Industrialization (past burning of coal).