Preparative centrifugation ? a new method for preparing pollen concentrates suitable for radiocarbon dating by AMS

Methods of preparative centrifugation eliminate many of the difficulties involved in preparing pollen concentrates from deposits rich in resistant organic material. Density centrifugation for the separation of pollen from a gyttja sample rich in resistant organic matter was tested. Combining centrifugations in two CsCl solutions, one of higher density and one of lower density than pollen, a pure pollen fraction was successfully prepared. Data on the isodensity and sedimentation rate of ‘fossilized’ recent pollen from twelve tree taxa are also presented, and the potential for separating a single taxon from pollen assemblages is demonstrated.