At least 5 g of the sample is sieved through the sieves (5.3) in at least two fractions.
The sieve fraction(s) >0,5 mm (or a representative part of the fraction) is applied as a thin layer to a suitable support and screened systematically under the stereomicroscope (5.4) at various magnifications for constituents of animal origin.
Это интересно
fraction – a portion of an unconsolidated sediment ... or of a crushed consolidated rock sample ..., or of a crushed ore or mineral sample. The fraction has been separated by some method, and is distinguished in some manner, from all the other portions (or fractions) comprising the whole sample being analyzed. A fraction is commonly defined by its particle size (grain size). The size limits of a fraction are not always expressed in units of linear measurement, but sometimes ... in more general, descriptive size designations (such as the clay fraction, the silt fraction, or the sand fraction).
