MOIiYBDENA-SILVER. 127 



of the amygdaloid from Faroe, containing the 

 Mesole and the pyramidal and prismatoidal Kou- 

 phone-spars. 



This is probably a variety of Chabasie, which is found 

 along with the other species in the above mentioned spe- 

 cimens. The following table contains the analyses of, 

 1. Mesole by BERZELIUS, 2. Chabasie from Fassa by ARF- 

 VEDSON, 3. Chabasie from the Giants Causeway by ARF- 

 VEDSON, and 4. Chabasie from Gustafsberg by BERZELIUS. 

 1. 2. 3. 4. 



Silica 47-50 43-38 49-07 50-65. 



Alumina 21-40 19-28 18-19 17'90. 



Soda 4-80 0-00 12-19 0-00. 



Potash 0-00 2-50 a trace. 1-70. 



Lime 7'90 870 0-00 9'73. 



Water 18-19 21-14 1973 19-90. 

 BERZELIUS observes that the Mesole was not quite pure, 

 but had a little of the rock attached to it. These analyses, 

 together with those of the other varieties of rhombohedral 

 Kouphone-spar and of Gmelinite, differ only in the kind 

 and proportions to each other of the alkaline base which they 

 contain. The substances themselves are not, all of them, 

 sufficiently known, to say whether, as it is probable, this dif- 

 ference is founded in really different natural-historical spe- 

 cies, as in the case of prismatic Feld-spar, Albite, and Labra- 

 dorite, or whether they should be comprised in one species. 



MOLYBDENA-SILVER. 



Molybdena-Silver. JAM. Man. p. 326. Molybdic Silver. 

 PHILL. p. 287. 



Rhombohedral. Cleavage, R, perfect. 

 Lustre metallic. Colour pale steel-grey. 

 Elastic. Not particularly sectile. Soft. Sp. Gr. 

 8-0., BREITHAUPT. 



