3 IP Elements of Mineralogy. 



fubtra&ed from that of the whole of the ore, 

 the remainder gives the weight of the marine 

 fait of mercury, and this being fublimate 

 corrofive, 100 gr. of it will contain 77 of 

 xnercury, ^nd fo in proportion; 



SPECIES IV. 

 ^Ulnerallzed by Sulphur. 

 Native Cinnabar. 



7. This is of different fhades, from a yel^ 

 lowifh to a deep red, and is found either pure 

 in hard, friable mattes, either fhapelefs or 

 cryftalized in cubes, and fometimes tranfpa- 

 rent, or intermixed with clay or done, or in- 

 terfperfed through the ores of other metals, 

 particularly thofe of filver or copper, or 

 jnartial pyrites ; its texture is either radiated, 

 ftriated, fcaly or granular. 100 parts of cin- 

 nabar contain about 80 of mercury, and 20 

 of fulphur ; artificial cinnabar contains a little 

 jnore fulphur, and hence its colour is darker; 

 its fpecific gravity is about 7,000 ; it fublimes 

 in clofe veflels, and in open, it is decompofed 

 ?ind volatilized when fufficiently heated ; it i? 

 infoluble in the nitrous and vitriolic acids ; it 

 |s fometimes contained in very fyeavy red or 

 |jrownilh red ftones or fand, 



8 ? To analyfe it in the moift way, its ftony 



matrix^ 



