M I N E R A L O G. Y, 
11 
clofely cooHned in different fubftances : fince 
garnets are generally found difperfed in 
other folid ftones, and oftentimes in the 
harder ones^ fuch as quartz and chert 
' SECT. LXIX. . 
I. Garnet, Granatus. 
' Which is a heavy and hard kind of ftone, 
criftailifing in form of polygonal balls, and 
is moftly of a red, or reddilh brown co- 
lour. 
A, Garnet mixed with iron, Gramtus mar^ 
tialis. 
* It is certain, tliat the metallic calces being mixed with 
other earthy fubftances, make great alteration in refpedl to 
their fufibiJity; and we know from experience, that the 
prefence of iron in the argillaceous, and moft particularly 
in the micaceous kinds, renders them fufible ; however, 
though there may be good reafons for confidering the garnet 
as a quartz impregnated with iron ; yet as quartz becomes 
lefs fuftbie by any addition of iron, of which the Swedilh 
Torrfien, (Se6l. ccxiii. in the note) a martial ore, commonly 
mixed with quartz, is an inftance ; and as even the fpecies 
of quartz naturally mixed with that metal, (Se£l. liii. A,') 
are far lefs eaftly fuftbie than the garnet ; it might perhaps 
be better to call the garnet a done of a diiferent order, until 
by fufficient experiments we may have reafon to reduce the 
number of the earths. Though if we fhould ever arrive at 
an. exafi: method of clafting in this refpcfl, perhaps the 
ceconomicai ufe of thefe bodies will rather require fuch a dif- 
tribution of them as (hall more regard their prefent exiftence, 
than that which they have been originally derived from. 
The garnet earth, fo far as I know, is not vet found, but 
in an indurated ftate ; and, as fuch, it is divided into the 
garnet, and into fhirl or cockle, and that in regard to the 
figure of their criftals, more than any thing elfe : though 
•their colour has alfo had fniie ihare in this divifton. I have 
here followed cuftom, which, p.erhaps, may have fome rea- 
son, however ill founded it be, 
I, Coarfe 
