We have developed a simple, rapid method to screen carbonates for survey applications, which provides radiocarbon dates with decreased precision at lower cost. The method is based on previous work by Longworth et al. (2011) and involves mixing pulverized CaCO 3 with Fe powder, followed by pressing into aluminum target holders for direct 14 C accelerator mass spectrometry (AMS) measurements. An optimum beam current averaging ~10% of those produced by >0.7 mg C graphite targets was obtained for

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... rbonate samples of 0.3-0.5 mg (0.04-0.06 mg C). The precision of the method was evaluated by measuring triplicates of 14 C reference materials, as well as by comparing results from this rapid method with results from high-precision AMS measurements on graphite (typically 0.2-0.3%). Measurement reproducibility was ~1.8% (1) for samples <10 ka BP, and it increased drastically for older samples. However, t tests on paired samples resulted in p values greater than 0.05, indicating a good correlation between this survey method and the conventional one. An average blank (calcite) of 0.0075 Fm (~39 ka BP) was achieved. The simplicity of the technique allowed us to process and measure 72 deepsea coral samples in less than 25 hr.