11 
some Minerals of the Zeolite Family. 
Silex, 50.65 Which contains of Oxygen, 25.44- No. of Equivalents, 9 
Alumine, 17.90 8.36 3 
Lime, 9.73 2.73 > j 
Potash, 1.70 0.29 1 
Water, 19.90 17.69 6 
The result of this analysis differs from that of M. Arfwedson, 
by an additional equivalent of silex-; but the mineral was form- 
ed upon a crust of quartz, which often penetrates the crystals, 
and I am persuaded that this circumstance is the cause of the 
excess of silex. 
The Red Stilbite sent also by Mr Allan, is the Stiibite Anamor- 
phique of Haiiy M.^Walmstedt, Professor of Chemistry at 
Upsal, has proved, that the Stilbite Anamorphique and Octode- 
cimale, have a composition differing essentially from that of the 
ordinary Stilbite f. The following is a comparison of the two 
analyses, 
Common Stilbite Stilbite Anamorphique 
by Hisinger. by Walmstertt. 
Silex, - - 58.00 59.90 
Alumine, - - 16.10 16,87 
Lime, - - 9.20 7.19 
Water, - - 16.40 13.43 
The formula of the first is CS^ + 3 JS^ -I- 6 Jq., and that of the 
last CS^ -b 4 AS^ + 6 Ag. The different quantities of water 
which these minerals contain, afford an easy method of distin- 
guishing them, since the one loses in the fire 3 hundreths of its 
weight more than the other. 
From these analyses, you will observe that the zeolites de- 
serve to be examined by chemists with much more attention 
than they have hitherto received. I am persuaded that they 
contain a great number of different combinations, which are at 
present confounded. 
I am, Sir, yours, &c. 
Stockholm, \ 
dth Ajjrii m^. f 
Berzelius. 
• The Heulandite of Mr Brooke, See this Journal^ Vol. VI. p. 112 .— -Ed, 
*1* * Mr Brooke has already, from crystallographic characters, separated the 
ordinary Stilbite from the two varieties above mentioned, and it is satisfactory to 
find the conclusions of this able mineralogist so strikingly confirmed by chemical 
analysis. See this Journal^ Vol. VI. p. 112.— Ed. 
