Granite Rock Standard Sample: NGRI-G

As a part of standard rock sample preparation program, NGRI has prepared a standard rock sample of granite for chemical analysis of granite rock samples using instrumental methods of analysis and to calibrate the instruments. International granite rock standards prepared by United States Geological Survey are no available and, thererore, it was felt necessary to prepare our own standards for different rock types.

The sample is homogeneous and gives reproducible values for all the major and minor oxides and ten trace elements. Replicate analysis at NGRI using XRF, AAS, Spectrophotometer and at other laboratories in USA and West Germany have given confident results. Proposed values for nine oxides and seven trace elements are given in this paper and the sample is offered to be used as a geochemical reference standard for granite samples.