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X-RAY ANALYSIS 



N. C. Schieltz 



Within the past half century the use of X-rays has been developed as an 

 analytical tool to an extent that today it is considered as one of the most versatile 

 and reliable methods of analysis, as well as a powerful research tool. X-rays can 

 be used equally well for diffraction studies or emission spectrographic analysis 

 to determine of which elements a substance is composed; how these elements 

 are combined to form molecules or how they are space packed to yield our 

 ultimate crystal structures. These analyses may be purely qualitative or they 

 may be designed to give quantitative results. The results of the analysis may be 

 recorded by conventional film methods or by the use of counters (proportional, 

 geiger, photo multiplier, etc.) combined with suitable strip chart recording 

 mechanisms. For a discussion of these methods the reader is referred to standard 

 books on the subject (Cullity, 1956; Klug and Alexander, 1954; Davey, 1934; 

 Bunn, 1946; Clark, 1955; Bragg, 1955; Buerger, 1942; Guinier, 1952; Henry, 

 Lipson & Wooster, 1951; Barrett, 1952). This discussion will be limited to such 

 information as is necessary for the identification of materials of interest to the 

 geologist. 



These methods are extremely advantageous since by means of them we can 

 determine not only which elements are present (with limitations) but also their 

 combinations while forming the various mineralogic species. Furthermore, the 

 methods are non-destructive, so that the same sample specimen can be used for 



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