Abstract: The methods of valuation by fractal volume (VFV) and valuation by integral volume (VIV)are commonly used in reserves calculation.However,they can not be interchanged arbitrarily,because there is an essential difference between the two methods.For technical reason,in the calculation of reserves,first we usually divide a large ore body into several segments and calculate the volumes of each,and then work out the sum of the volumes as the bulk volume of the ore body.In these calculations,the simple volume formulae for a cone and a sectional conoid are applied,which result in a difference between the two methods.Theoretically,when a ore body whose shape is similar to across-section frustum of acone is divided into some segments and the volume of the segments or the whole body is worked out by the sectional conoid volume formula,the sum volume of all the segments worked out by VFV is smaller than the total volume value calculated by VIV.The difference is related to the number of the divided segments.The larger the number is,the more remarkable the difference is.Therefore,the value of the reserves will be smaller as compared with the re ality.According to A.P.Prokofiev,the sum of the segment volumes must be checked with the whole volume of the integral block of the same geological cross-section.It is necessary to rectify the volume value worked out by VFV for each segment so that the deviation could be reduced to minimum.Furthermore,the method and formula for rectification are developed.With that,the veracity for the reserve calculation can be remarkably improved,and the ore resources would be developed and utilized more economically and reasonably.