Mining review . elted, whether rich or poor, should be included ni thesample. The quantity taken might amount to one pound per foot of lodewidth; but the nature of the ore body and the distribution of the values(whether uniform or irregular) must be considered when deciding on thesize of the sample. With uniform values the interval along the lode can begreater and the amount broken less than if the lode carries irregular values,as in the case of a lode carrying coarse gold. 32 THE PROPER WAY TO REDUCE THE SIZE OF A SAMPLE. Such a sample, if of any considerable size, should then be broken intos
Mining review . elted, whether rich or poor, should be included ni thesample. The quantity taken might amount to one pound per foot of lodewidth; but the nature of the ore body and the distribution of the values(whether uniform or irregular) must be considered when deciding on thesize of the sample. With uniform values the interval along the lode can begreater and the amount broken less than if the lode carries irregular values,as in the case of a lode carrying coarse gold. 32 THE PROPER WAY TO REDUCE THE SIZE OF A SAMPLE. Such a sample, if of any considerable size, should then be broken intosmaller pieces, well mixed, and quartered down. Quartering down meansthat the broken ore, after mixing, is piled into a cone on a floor or cloth,and that the cone is flattened and subdivided into four parts by two cuts atright angles. If the ore is sufficiently broken and mixed the sample obtainedby taking the two opposite quarters, A A, has a value equal to the rejec-tions B B, shown in the following diagram:—.
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