MINERALOGY. _ 
4. It is pretty fixt in the fire ^ ^ but together 
with the fulphur and arfenic, with which 
its ore abounds , it is fo far Yolatilcj as to 
rife in form of hairs and branchesj if in 
the calcination it is left without being 
ftirred. 
5. It calcines to a green cajx; , 
6. This calx is not very fufiblcj but however 
tinges glafs of a tranfparent reddifh brown^ 
or jacinth colour. 
7. It diflblves in aqua fortis^ aqua regia, and 
the fpirit of fea-falt, but more difficultly in 
the vitriolic acid, tinging all thefe" folutions 
of a deep green colour. Its vitriol is of 
the fame colour 1 but the colcothar of this 
vitriol, as well as the precipitates from the 
folutions, become by calcination of alight 
green colour. 
8. Thefe precipitates are diflblved by the 
fpirit of fal ammoniac, and the folution has 
a blue colour^ but being evaporated, and 
the fediment reduced, there is no copper^ 
but a nickel regulus is produced. 
9. It has a ilrong attradion to fulphur ; fo 
that when its calx is mixed with it, and 
puts on a fcorifying teft under the muffcl, 
it forms with the fulphur a regule: This re- 
gule refembles the yellow fteel-grained 
copper-ores, and is hard and Ihining on 
its convex furface. - 
10. It unites with all the metals, except 
quickfilver and filver. When the nickef 
regulus is melted with the latter, it only 
adheres clofe to it, both the metals lying 
near one another on the fame plane ; but 
they are eafily feparated with a hammer. 
Cobalt has the ftrongeft attradion to nickel, 
after 
