Coning and quartering

Coning and quartering

Coning and quartering is a method used by analytical chemists to reduce the sample size of a powder without creating a systematic bias. The technique involves pouring the sample so that it takes on a conical shape, and then flattening it out into a cake. The cake is then divided into quarters and two quarters which sit opposite one another are discarded, whilst the other two are combined and constitute the reduced sample. The same process is continued until a reaonable amount of material is left behind. Analyses are made with respect to the sample left behind.

=See also=
Sub-sampling

=References=

*cite web
title = IUPAC Coning and Quartering (in analytical chemistry)
url=http://www.iupac.org/goldbook/C01265.pdf
accessdate = 2007-11-09


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