478 



PROE. B. KOTO ON OCCURRENCES OP 



notes that there are two interesting rocks in the crystalline-schist 

 system of Japan, one of which is " ein echter durch charakteristische 

 rothe larbung kenntlicher Turmalinschiefer, der nnter dem Mikro- 

 skop schongefarbte starke dichroitische langgestreckte Krystalle 

 zeigt." The original specimens from which E. Naumann penned the 

 above-quoted statement were kindly placed at my disposal by the 

 Geological Survey of Japan. On examining the various slides the 

 writer was firmly convinced that here we have to do with true pied- 

 montite, and not a tourmaline ; and the analysis given above confirms 

 the writer's view. 



(c) Geographical Distribution of Piedmontite. — The mineral pied- 

 montite is not of common occurrence. In treatises on mineralogy 

 we find only two typical localities up to the present : the one is 

 St. Marcel, near Aosta, in Piedmont, Italy, where it occurs, as a rare 

 mineral, together with other manganese ores ; the other is Jacobs- 

 berg, in Wermland, Sweden, where it is found localized within a 

 limestone. In both cases, as it seems to me, piedmontite occurs as 

 a rare mineral, and it is by no means abundant enough to form an 

 independent rock. 



Its extensive occurrence in Japan is somewhat remarkable, and is 

 probably unequalled in other parts of the world ; the manganepidote 

 and quartz constitute the piedmontite-schists, and it is also an acces- 

 sory component in glaucophane-schist *. Geologically speaking, its 

 occurrence is confined to the same horizon as the glaucophane, i. e. 

 the lower part of the chlorite-schist series of the Archaean complex. 

 This unique piedmontite-bearing rock is of unexpectedly wide dis- 

 tribution, and constitutes, indeed, an essential member in the Archaean 

 system of Japan. The subjoined are some out of many of the 

 typical Japanese localities of manganepidote : — 



SikoTcu Island. 



1. Otakisan, near the city of Tokusima, Awa province. 



2. Bessi Copper-mine, in Uma Gori, Sanuki province. 



3. Cbihara Copper-mine in Siufu district, Kitanada in Kami- 

 Ukima district, Uchinoko and Haya in Kita district, Iyo province. 



Main Island. 



4. Minano, Simo-Tano and Yori, Chichibu district ; Ogawa, in 

 Hiki district, Musasi province. 



5. Umenokidaira and Sambagawa, Kanra district, Kozuke pro- 

 vince. 



6. Misaka, in Iwamae district, Iwaki province, &c. 



(d) A peculiar Epidote. — There is still another variety which 

 may be conveniently described on the present occasion. In speaking 

 of the glaucophane-schist in his other paper t, the writer has already 

 given a brief notice of the presence of a remarkable piedmontite. 



* Journal of Science College, Imperial University, Tokyo, vol. i. part 1. 

 B. Koto, ' A Note on Glaucophane,' pp. 85 ei seq. 

 t Loc. cit. p. 85. 



