Petersburg to build a highly sensitive mass spectrometer and measured the He concentrations in a selection of ancient gold objects. Some objects described in this earlier publication are also included in the present work, because we obtained additional He data for them, and, in particular, because U and Th analyses were performed for these objects, for which, in our earlier investigation, we had to employ average U and Th values.
This time may be consistent with the Palaeozoic-Mesozoic (542 – 65.5 Ma) intrusive rocks of the gold mineralisation (Beda Hofmann, private communication).
In the present work, we report additional data, in particular the U and Th concentrations for the Childebert ring, which were not yet available for our previous publication. The U and Th analyses used in this work were performed by six different laboratories.
In most cases, multiple analyses for a particular gold object, and numerous tests and blank measurements had to be carried out.
The objects to be tested in this study are listed in Tables 3 and 4.
In most cases, the purported origin and age have been indicated by the owners of the objects.