Moment and graphic size parameters were computed on 420 surfical sediment samples from Lake Geneva (Switzerland). The sediment ranges from sand to clay-size and comprises a significant amount of precipitated silt-size calcite. Comparison of parameters shows that mean, sorting, and skewness may be estimated either by moment measures or by Folk and Ward's descriptors, without essential differences in interpretation. As for kurtosis, moment and graphic parameters provide different information, and both should be used separately as interpretive tools.