Epistolite, a new mineral, 



by 0. B. Boeggild. 



Among the minerals, which Gustav Flink brought from 

 Greenland in the summer of 1897 ^) were some silverwhite 

 plates, which he supposed to be brucite, but on analysis they 

 have proved to be an absolutely new mineral, which seems 

 to have no relation to any other. The name has been derived 

 from еттшто?.-^, a letter, on account of the mineral's flat rect- 

 angular form and white color. 



The quantity of epistolite collected has been found in four 

 different localities, all in the neighborhood of Julianehaab in 

 Greenland. Flink states in his above mentioned report that 

 it has been found at Tutop Agdlerkofia and Nunar- 

 siuatiak, two places on the Northern Side of the Firth of 

 Tunugdliarßk. I have also found it on the pieces brought 

 from the bottom of the Firth of Ranger dinar suk and from 

 the small island Kekertanguak situated in the innermost 

 part of this Firth. The surrounding rock is always nephelite- 

 syenite in which the epistolite is found partly in the pegmatitic 

 veins, partly in masses of marblelike grained albite. 



Crystalline form. Crystals with free faces projecting into 

 a cavity have only been found on one of the pieces. However 

 the condition of the faces made the determination of angles very 

 difficult. It was impossible to use the reflecting goniometer, the 



') Gustav Flink: Berättelse om en Mineralogisk Resa i Syd-Grönland 

 sommaren 1897. Meddelelser om Grønland. XIV. 1898, p. 247, 257. 



