MINERALOGY. 
have been called Marble, although the Italian 
mafon himfelf knows extremely well how to dif- 
tmguifh a Marble, a Jafper, and a Granite, from 
one another, giving the two laft names only to 
marbles of fuch colours as thofe fpecies generally 
have, when he either cannot get any real ones of 
thofe harder ftones, or will not give himfelf the 
trouble to polifh them. This confufion in the 
names may, however, in regard to this fyftem be 
tolerated, fince thefe three different fpecies of 
ftones, viz. the limeftones, the jafpers, and the 
granites, are here feparately defcribed : but fince 
they cannot all be worked in a like manner, nor 
do they equally refill the violence of time, they 
deferve to be known by the architeds in a clearer 
manner, and by feparate names. 
A yet lefs confufion is that of the Saxqm, which, 
tho’ compounded of limeftone and ferpentine is 
called Marble, not only when it contains a greater 
quantity' of the limeftone, as the marble from 
Kolmofden in the province of Oftrogottiand, but 
alfo when the ferpentine predominates, as in the 
marble called Pozzevera de Genoua^ and alfo a 
kfnd of green marble from Spain, becaufe this 
kind of ftone is as eafy to cut and work as a true 
marble, although the ferpentine is fomewhat 
fofter, and eafier to polifh. 
The calcareous fpar (Se6l. x.), and its cryftalll- 
fations (Sed. xi.), are more difficult to be burnt 
into lime, than other limeftones ; they are there- 
fore of no great ufe in architedure, any further 
than that they may be employed in making grot- 
tos : Nature has alfo made the quantity of this 
kind proportionable to its ufe, 
^ What our Author calls Serpentine, is a fpecies of ne^ 
phridc, and of the clafs of Talcs. D. C. 
^ ^ But 
