‘ 
Tungsten and Tellurium. 405 
admitting this to be the fact, there is a manifest impropriety in 
offering to the public, as a medicine, an article which cannot be 
used as such. Probably the proprietors of this manufactory 
are not aware of the real nature of the case, and of the facility 
with which, by a little additional trouble, they could separate 
the useful and valuable material, from that which is at least 
useless, and which might also be pernicious. : 
South Carolina College, March, 1819. 
Arr. XVII. Additional Notice of the Tungsten and Tellurium, 
mentioned in our last Number. 
Part. I. Description of the ore. 
Coror, dark brown, almost black; brittle; powder a 
lighter shade of brown than the mineral; hard, scratches glass, 
scintillates with steel, with a red spark; a degree of polish 
produced, where the steel strikes, and where it is impressed 
upon it. 
Structure compact, in some places slightly porous; lustre, 
generally dull, sometimes glimmering, and almost resinous. 
Crystals octahedral. Specific gravity of three massive 
pieces, 5.7,6. and 6.44; mean, 6.05 nearly; probably that of 
the crystals would be higher. 
Infusible by the blow-pipe even with borax, and does not 
by strong ignition impart any color to it or to potash; not 
magnetic, even in fine powder, nor after being heated red hot 
on charcoal, and in contact with burning grease. 
Many sz “ies decrepitate violently under the blow-pipe. 
When heated on coals in pieces of considerable size, they often 
explode with a smart report, and are thrown in fragments 
sometimes several yards from the fire. 
Gangue quartz; accompanying minerals in the same vein 
native bismuth, native silver, galena, iron and copper pyrites, 
much magnetic pyrites, blende, &c. 
WOE Ns; WO. 4, 12 
