M I N E: R A L 6 G t. 17^ 
its metallic form, and in form of a calx or 
glafs. 
3. It does not amalgamate with quickfilver, 
by itfelf, but only by means of the acid of 
common fait after a long trituration. This 
metal is therefore really feparated from 
gold by amalgamation, at thofe places 
where it is found i and without this qua° 
lity, it would be very difficult to feparate 
it. 
4. It is harder and lefs coherent than gold. 
5. It is heavier than gold ; and therefore the 
heavieft of all bodies hitherto difcovered : 
For though the fpecihc gravity of platina, 
in the hydroifatical experiments made by 
Dr. Lewis, is found to be to water only as 
17,000 to 1000; yet, when melted with 
other certain metals, its ipecilic gravity 
has, by an exabl calculation, been found 
to be confiderably augmented, even fo 
much as to 22,000. 
B. DifTolved in aqua regia, and precipitated 
with tin, or with a folution of that mietalj 
it yields no purpura miner alls. 
Except thefe, this metal has the fame 
qualities as gold ; but it cannot, on ac- 
count of its refraflorinefs in the fire, be 
worked oft pure on the cuppel, nor like- 
wife can it be worked with antimony ; be« 
Caufe, before it is rendered perfedlly pure, 
it cools, grows hard, and retains always 
fome part of the added metals. It is 
brought to us only in its native ftate, in 
fmali, irregular, rugged grains ; and it is 
yet uncertain whether it is found naturally 
mineralifed. The Platina is brought to 
N 2 Europe 
