A S Y S T E M OF 
Loofe and friable, Pulverulenta Jive friahU 
Us, Mountain blue, Ccemkum montanum^ 
Germanice, Berghlau, 
This difiblves in aquafortis with effervef- 
cence. 
SECT. XXXV. 
B, Indurated, indurata, 
i. Pure calcareous earth mixed with calx of 
copper. Armenian ftone. Lapis Armems* 
Such, according to the defcription of 
authors, ought the nature of the ftone 
called Lapis Armenus to be, though the 
druggifts fubftitute in its ftead a pale blue 
Lapis Lazuli, free from Marcafite, 
SECT. XXXVI. 
Gypfeous Earth united with calx of Cop- 
per, Terra gypfea Venere mhta. Is of a 
green colour, and might perhaps be called 
Tiirquoife ore, ov Malachites ; though I do 
not know if all forts of Turquoife ore are 
of this nature. 
a, Semi-tranfparent, is found at Ardal 
in Norway 
® By we know, that alcaline falts produce a blue 
cotar with copper, which is changed into green, as Toon as 
any acid is added ? and from thence the reafon is obvious, 
why a green colour may be found among calcareous copper 
ores, when the vitriolic acid is in the neighbourhood of 
it. 
SECT. 
