从要取样的批次中提取一定数量的增量。将增量混合形成代表性样品（散装样品）。从代表性样品中，通过重复还原制备最终样品。

A certain number of increments is taken from the batch to be sampled. The increments are mixed to form a representative sample (bulk sample). From the representative sample a final sample is prepared by means of replicate reductions.