Mb 



The meltingpoint, determined after the dynamical method (element 

 III), was found : 



14463 M. V. 

 14481 M. V. 



Mean 14472 M. V. ± 10 M. V. (without correction j ; 

 after correction, the meltingpoint can be fixed at 1410° ± 1° C. (G.Th.). 

 After the statical method, the meltingpoint was determined at 

 14450 M. v., corresponding to 1410^0. The small excess of Al,0^ 

 has evidently caused an increase of the meltingtemperature, of about 

 9° C. The crystallized product again was shown to be /:?-spodumene 

 {n =z 1,519) ; a photograph of it, taken between crossed nicols is 

 reproduced in fig. 4. 



3. An analogous result was, in both ways, obtained with a pre- 

 jtaration, prepared from Li^SiO^, AI^O^ and SlO^. Analysis of this 

 product gave the following data: 



I II Calculated : 



SiO, 64,7 7„ 64,48 7„ 64,6 »/„ 

 Al^O, 28,4% 28,5 7„ 27,4 7o 

 Li^O 6,9 7„ 7,1 7„ 8,0% 



The content of SiO^ is here the right one, but the AJ^O^ is 17o 

 too high. The jneltingpoint determinations gave as a mean value:' 

 14456 M.V. (uncorr.) after the dynamical method, and about : 14450 

 M. V. after the statical method. The meltingpoint is therefore : 

 1409° C. (G.Th.). 



4. Most deviating from the couiposition : LiAlSi^Oe, was a pre- 

 paration, obtained from the melting together of Li^CO^, SiO^ and 

 AIJJ^. Analysis gave the following numbers: 



I II Calculated : 



SiO, 64,44% 64,88 7„ 64,6% 

 Al^O, 27,09 7„ 27,17% 27,4% 

 Li,0 8,47% 7,95 7„ 8,0 7„ 

 ' Evidently it contains about 0,21 7o Li J) too much. 



After the first method the meltingpoint was found at 14552 M.V. 

 (uncorr.), and after the statical method : 14550 M.V. The (rue melting- 

 point can thus be put at: 1417° C. (G.Th.). 



§ 10. Although in most cases perfectly colourless products were 

 obtained, which evidently were identical to and independent of the 

 particular manner of preparing them, and which all represented the 

 /5-modification, — we succeeded however in several cases in obtaining 

 beautifully crystallized preparations, which locally or also totally were 



