204 Professor Gmeiin's Analysis of a 



pidolite, therefore, cannot be considered as a mixture of com- 

 mon (potash) mica with lithion-mica. Amongst the different 

 species of mica which occur in the same tract, I have disco- 

 vered some which bear a great resemblance to Lepidolite com- 

 monly so called, being composed of small lamellae agglutinat- 

 ed to larger masses. ; others, on the contrary, possessed of si- 

 milar external characters, contained no lithion. The easily 

 fusible micas in the Dolomites of St Gotthard, mentioned by 

 M. Cordier in his Treatise on Lepidolite, are most likely li- 

 thion-micas, but I have had no opportunity of examining them. 



It may be observed, that the presence of lithion in a mine- 

 ral seems to exclude a larger quantity of iron ; I made this 

 observation, when I examined several species of tourmaline, of 

 which those that contained much iron never contained lithion ; 

 and even the black tourmaline, which occurs along with li- 

 thion-mica near Chursdorf, can at least contain no large quan- 

 tity of lithion, as it does not tinge red the flame of an oil lamp. 

 On the other hand, lithion seems to associate more readily 

 with manganese, as may be seen in the tourmalines and micas 

 that contain lithion. The lithion-micas contain likewise a 

 larger quantity of fluoric acid than common micas. 



In the formations of the neighbourhood of Penig, lithion 

 seems to be considerably diffused. Near Hartmansdorf, be- 

 tween Chemnitz and Penig, a peculiarly formed quartz is 

 found in serpentine, composed of agglutinated round concre- 

 tions, whose fracture exhibits fibres diverging from a common 

 centre. Splinters of this quartz tinge the flame somewhat red, 

 which does not happen with a splinter of rock-crystal when 

 treated in the same manner. I could not, however, decided- 

 ly prove by analysis the presence of lithion in this quartz. I 

 obtained 99.57 p. c. of silica, with traces of iron and alumine, 

 and equivocal traces of lithion. In a manner a little more de- 

 cided, this alkali is manifested by the blow-pipe in the Anda- 

 lusite, which formerly was found in a mass of granite imbed- 

 ded in Weiss Stein, in a valley between Penig and Rochsburg. 

 But in a most unquestionable manner lithion is discovered in this 

 way in a substance which is found adhering to the quartz already 

 mentioned in small particles. This substance has a wax-yel- 

 low colour, is unctuous to the touch, very soft, a little trans- 

 parent, and may be spread with a knife upon paper. It 



