MINERALOGY, 189 



reddifh brown, and afterwards of a tranf- 

 parent green or fea-green colour. 



f. It difiblves in all the acids ; vL ;. The acids 

 of vitriol, fea-falt, nitre, and the vegeta- 

 ble •, and likewife in all alcaline folutions. 

 That it; becomes rufty, and tarnifhes in the 

 air (a confequence of a former folution)^ 

 depends very much on ibme vitriolic acid 

 which is left in the copper in the refining 

 of it. This metal is ealier dirTolved when 

 in form of a calx than in a metallic ftatev 

 efpecially by the acids of vitriol and fea- 

 falt, and the vegetable acid. 



g. Vitriol of copper is of a deep blue colour* 

 but the vegetable acid produces with the 

 copper a green fait, which is verdigrife. 



h. It can be precipitated out of the folutions 

 in a metallic ftate \ and this is the origin 

 of the precipitated copper of the mines, 

 called Ziment copper. 



i. It is not eafily amalgamated with quick- 

 filver ; but requires for this purpofe a very 

 flrong trituration, or the admixture of the 

 acid of nitre. 



k. It becomes yellow when mixed with zink, 

 which has a flrong attraction to it, and 

 makes brafs, pinchbeck, &c. 



/. It is eafily dirTolved by lead glafs, which 

 lad is coloured green by it. 



m. When this metal is expofed to the fire, it 

 gives a green colour to the flame in the 

 moment it begins to melt, and continues 

 to do fo afterwards, without lofing any 

 thing considerable of its weight. 



7*. It requires a flrong degree of heat before 

 it melts, yet is it a lefTer degree than for 

 iron. 



SECT, 



