86 
CONTRIBUTIONS TO MINERALOGY. 
| mi 
Si0 2 
Al.,<>, 
Ag 2 combined. 
Ag 2 free 
CaO 
H 9 
40. 45 
10.24 
20. 48 
. 93 
7.84 
34.70 
18. 54 
32.30 
3.91 
2. 50 
. 39 
7.32 
99.66 
B. reduced. 
36.25 
10.36 
33. 73 
2.61 
.41 
7. 64 
100.00 
Moleculai 
ratios. 
100. 
31. 
24. 
Both preparations were very dark, showing that a quantity of fre 
silver oxide had been deposited. The compound formed is easil 
decomposed by warm dilute nitric acid, giving a perfectly clear solj 
tion which gelatinizes upon evaporation. Under the microscope, 
showed perfect crystallization. 
Neglecting free silver oxide, residue B gives the following formuli 
24Ag 2 0, 8CaO, lNa 2 0, 31A1 2 3 , L00SiO 2 , 70H 2 O, 
or, combining monoxide bases, 
R' 66 Al 62 Si 1M SM , 70H 2 O, 
which corresponds roughly to the formula R 2 Al 2 Si 3 O 10 . 2H.,0. T 
ratios are not so good as could be desired, but are close enough to she 
that this compound has probably been formed. 
One thallium derivative was made by heating natrolite in a seal 
tube with six times its weight of thallous nitrate for forty-eight hou 
at 250 -290° C. The analysis gave the following results: 
Residue. 
Si0 2 .. 
A1 2 3 - 
Tl,<>.. 
( !a( ) . . 
Na 2 . 
H 2 0- 
H 2 0+ 
26.10 
15. 59 
55. (54 
.67 
.31 
.51 
. 66 
99. 51 
Moleeu' 
ratios 
Ml 
9 
