308 B. KOTO 



Comparison with other Specimens of Piedmontite. 



A comparison of the result just stated with analyses of the 

 Swedish and Alpine Epidotes^^), shows our mineral to be in some 

 particulars markedly different from both of them, although there is 

 a general resemblance throughout. The Japanese Piedmontite indeed 

 forms just the link between those of Jacobsberg, in Sweden, and of 

 St. Marcel, in Piedmont. Mr, ïakayama informs the writer that he 

 has not yet been able to decide whether in our specimen the 

 Manganese exists as the sesquioxide or monoxide or (thirdly) both 

 together. 



As is well known, Igelstrom suggests that the Swedish mineral 

 contains manganese as the monoxide, while others are of opinion that 

 in the Alpine Epidote there exists only the sesquioxide. Some 

 mineralogists, therefore, hesitate whether they should be put together 

 as the same variety. (^) The writer is unfortunately not able to 

 express himself more decisively on this point, and awaits a more ex- 

 tended research. 



Being of a beautiful rosy-red colour and of a highly pleochroic 

 character, and having a needle-shape, the Piedmontite is usually 

 confounded with a Toiu-maline, and as such was formerly regarded by 

 us. Dr. E. Naumann(3) says there are two interesting rocks among 

 the crystalline schists of Japan; the one is "ein echter durch 

 charakteristische rothe Färbung kenntlicher Turmalinschiefer , der unter 

 dem Mikroskop schöngefärbte starke dichroitische langgestreckte 

 Krystalle zeigt." The original specimens from which E. Naumann 

 had drawn the above-quoted conclusion were kindly placed at my 

 disposal by the Geological Survey of Japan. An inspection of the 



(i) llammelsberg, ' Miueralchemie,' 2te Auflage, p. 595. 



(2) Naumauu-Zirkel, 'Elemente der Mineialogie/ 12te Auflage, p. 577. 



(3) Uebcr deu Bau uud die Eutstclumg der japauisoheu luselu, Berlin, 1885, p. 10. 



