

0. D. Allen on Cae 



ium and RuhklU 



2Z^ 



omi.e fin excellent fieUl fo 

 groniKJ, the neijrhborhoo 



r the best qnaliti 

 of the sea, and tl 



)iktor wa.ires. Expeiiiiien 



hnients. Thev ^^o.•^«hi] 



•t'7lio!;"''tii^n'thi- 

 nportant claim upon t 



nt m the Shcllickl 



The discovery of the presence of the new elements rubidium 

 ^nd caesium in several varieties of European lepulolite, made it 

 ^ sul.ject of interesting inquiry to ascertain whether American 

 l^l'idolite would not also serve as a source for these rare metals. 



A preliminary experiment made last autumn by Mr. John M. 

 I^lake and myself, having shown that the lepidolite from He- 

 ^wn in ilaine con'tains these alkalies in comparative abundance, 

 "^ was led to visit that locality, and there obtained the material 

 winch served for the following investigation. _ _ 



Lepidolite occurs at Hebron in large quantity, in a coarsely 

 crystalline o-ranite associated with red and green tourmaline and 

 albite. It has a granular, and at the same time foliated, crystal- 

 Ji'ie structure, a paie rose to violet color, and very closely re- 

 sembles the lepidolite of Penig in Saxony, and like that is also 

 associated with the rare species amblygonite.* This locality is 

 only eight miles from that in Pai'is, which has long been known 

 to mineralogists. 



Preparation of the salts of Caesium and PoMdimn from the He- 

 ^on Lepidolite.— The process used for decomposing this mineral 

 ^as based upon that employed by Prof J. Lawrence bmith for 

 the determination of alkalies in silicates. Ten parts of the pul- 

 verized lepidolite were first mixed with forty parts of coarsely 

 powdered quicklime; a mixture of enough ^^^nte^ to slake the 

 quicklime, with hydrochloric acid sufficieut to form irom six to 



» This Journal, [2], xxxiv. 243. 



