F. W. Clarke on a new process in Mineral Analysis. 177 
As far as concerns the complete resolution of any mineral, 
pure, finely pulverized cryolite may be substituted for fluorid 
slags, and cinders, The perfectly white translucent specimens 
of eryolite should be chosen for, this purpose. 
Hither the bisulphate of potash or of soda may be used, and 
although neither seems to possess any advantage in point o 
thoroughness, the potassa salt appears to be the most readily 
fusible, and is therefore to be preferred. 
The following are the advantages that I claim for this process, 
First. Speed. Among the different ‘minerals upon which I 
have tested the action of this mixture, I have found no case 
where I was obliged to heat longer than five minutes, and many 
fusions are complete in three, and even less. 
When bisulphate of potash alone is used for a similar purpose, 
it is usually necessary to heat for from half to three-quarters 
of an hour; and even then in the cases of emery, chromite, and 
some other minerals, it is almost impossible to obtain absolutely 
complete resolution. 
y my process, even when the second fusion with sulphuric 
acid is necessary, not more than twenty minutes should be con- 
sumed in both fusions and the time for cooling between them. 
. In | 5 
of the mineral is absolutely perfect. Furthermore, all the sil- 
pared, cannot be preserved in glass vessels. 
Am. Jour. Sct.—Szconp Serres, Vou. XLV, No. 184—Mancu, 1868. 
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