Which is the best Be carrier for Be/Be accelerator mass spectrometry?

Commercial Be solutions used for chemical preparation of samples for accelerator mass spectrometry contain the cosmogenic long-lived radionuclide Be at elevated but different Be/Be levels. Within a systematic study of recently produced solutions, comparison to published data and new data on customised solutions from minerals, we recommend - if no customised solution is available - the Be solutions from Australian Chemical Reagents (ACR) or from LGC. They contain Be/Be at the 3.4 × 10 level, which is still suitable for the majority of Earth science applications, compared to customised solutions at the 10 level for lowest-level studies. Commercial solutions from Scharlab having different lot numbers, i.e. an identification number assigned to a particular lot of material from a single manufacturer, vary in Be/Be by up to a factor of nine. Hence, it seems an advisable strategy to buy a bigger quantity of a single production batch (such as 10 × 100 ml bottles of Be at 1 g l) and have them tested once at any AMS facility before first use.•The best Be carrier for low-level Be/Be applications is a customised one from minerals like phenakite.•The best Be carriers for medium- and high-level Be/Be applications are currently from Australian Chemical Reagents (ACR) or from LGC.•As Be carriers from Scharlab of different batches (LOT) contain Be/Be at different levels, it is advisable to buy a bigger number of bottles of the same LOT of commercial carriers after being identified to have reasonably low isotope ratios.