-°)14 Y. KIKTJCHI. 



The following' article is an account of the results which have 

 been obtained principally by the study of the specimens collected 

 from the bordering; region of the Provinces Ivödsuke and Shimotsuke, 

 along' the Watarase-gawa, where the mineral is developed in its most 

 typical and fresh state. Previous to the discovery of this occurrence 

 the attention of geologist was drawn to an interesting pseudomorphic 

 mineral found imbedded within a dark slate developed at the granitic 

 border, near the town of Kameoka in the Province of Tamba. It is 

 always found in a prism of hexagonal form, apparently cleaving par- 

 allel to the base, and consisting essentially of a greenish coloured mica. 

 It is generali v known as Salcura-ishi (cherry-stone), as its hexagonal 

 cross section presents a radial arrangement like that of a flower. 

 With regard to the nature of this pseudomorph, nothing definite 

 was known, for the original mineral which had given rise to 

 it, was not discoverable at or near the locality mentioned. It was 

 generally supposed to have been derived by alteration from some 

 such mineral as Andalusite. Close examination showed, however, 

 that there is a striking analogy of structure existing -between this 

 pseudomorph and the fresh specimen developed at the contact zone of 

 the Watarase-gawa region above referred to. Here also crystals 

 occur in a dark slate. They were proved to have the essential 

 characteristics of Cordierite, and on being altered gave rise to a 

 pseudomorph analogous to the " cherrv- stone " of Tamba. 



Dr. Geerts* gives the description of Sakura-ishi under the 

 variety of ' Chlorite hexagonale et lamellaire. ' It is mentioned as 

 having a pale rose ( ?) colour, and consisting of elongated hexagonal 

 prisms made up of tender and flexible lamina?. His specimen is said 

 to have come from Prov. Mikawa. 



The occurrence of Cordierite in the Watarase-gawa region was 



* Les produits de la Nature, Japonaise et Chinoise, p. 433. 



