Abstract

The consistently increasing need of obtaining information and data about the trace element content in geological material as applied to exploration as well as the investigation of the weathering process of ores demands the utilization of the semiquantitative spectrographic procedures. These procedures provide such data both rapidly and at a relatively low cost. The laboratories of the Companhia de Pesquisa de Recursos Minerais (C.P.R.M.), Brazil, use methods of semiquantitative spectrographic analysis to obtain this kind of information. The work is based upon the previous studies described by Oda and others and Grimes and Marranzino.

Spectrographic Procedure for Analysis of Powdered Samples of Unknown Origin

H. E. Biber and S. Levy
J. Opt. Soc. Am. 47(5) 381-385 (1957)

Sampling, Mixing, and Grinding Techniques in the Preparation of Samples for Quantitative Analysis by X-Ray Diffraction and Spectrographic Methods*1

James W. Ballard, H. I. Oshry, and H. H. Schrenk
J. Opt. Soc. Am. 33(12) 667-675 (1943)

A Step-Sector for the Astigmatic Spectrograph

Ralph E. Thiers
J. Opt. Soc. Am. 40(12) 849-851 (1950)

Interpretation of Data Obtained with Spectrophotometers of the Polarizing Type

Robert D. Nutting
J. Opt. Soc. Am. 25(7) 211-215 (1935)

Six-Meter Focal Length Ebert-Type Infrared Spectrograph. Part I. Details of the Spectrograph

K. Narahari Rao and Harald H. Nielsen
Appl. Opt. 2(11) 1123-1126 (1963)