442 On the Assay of Minerals by means of the Blowpipe. 
Boiling.—I1s when a mineral entering into fusion presents the 
appearance of ebullition, like borax, basaltic hornblende, &c. 
Vegetation.—In some instances a mineral presents the forms 
of buds, branches, &c. like borax, mesotype, gadolinite, preh- 
nite, &c. ’ 
Rounding of the edges, as in talc, &c. 
Varnishing, as in some saurolites, &c. 
Fritte is when certain molecules are fused and others are not, 
as in the rock composed of quartz and feldspar; the fritte in 
this case affords a method of discovering a mixture which other- 
wise would not be apparent. | | 
Scorification is when the whole mass passes into imperfec 
fusion, so as not to form one but several globules, as in certain 
chlorites. 
Complete fusion is when the whole mass becomes completely 
fluid, and forms globules or pearls. 
Crystallization—When a fused mineral assumes upon cool- 
ing a regular form, like the phosphate of lead, carbonate of 
soda, &c. 
Changes which attack the form and substance itself. 
Combustion or oxidation —When all the parts of a mineral, 
or some of them, are combined with exygen, hence result the 
following phenomena : 
Consumption.—Slow combustion and volatilization of the 
combustible particles, without flame or smoke, like the an- 
thracite. 8 cr 
Inflammation.—Rapid combustion with flame, like coal. 
Dissipation in smoke.—V olatilization of the combustible parts, 
with visible smoke, which is condensed, and adheres to the cold 
bodies, like coal, native antimony, &c. 
Calcination.—Conversion of a mineral into a metallic oxide 
in an earthy form: this change may be complete, or only on the 
surface. 
Vitrification.—Conversion of a mineral into a vitreous me- 
tallic oxide. 
Carbonizxation—Conversion of a mineral into charry matter, 
like coal. 
Incineration.—Conversion of a mineral into ashes by the ef- 
fect of-combustion. It may be manifested, either at the surface, 
as in the kohleblende, at the beginning of the experiment, or in 
the whole mass, as in the braun kohle. 
Reduction is effeeted by taking away the oxygen from an acid, 
or other mineralizer, like the carbonate of lead, tin ore, cinna- 
bar, &c. 
We ought also .to observe the circumstances of the other 
phenomena which are presented during the course of the ex- 
periment : 
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