[ 3o8 ] 
fufiony but gives the ftone a dark, and fometime^ 
a deep black colour, which always is the character 
of iron.. A Miner a ferri calciformis fur a cryftal- 
lifata^ is commonly of a red colour : This being 
expofed to the flame, becomes quite black,, and is 
then readily attra 61 :ed by the loadftone, which it 
was not before. Befides thefe figns, the iron dif- 
covers itfelf, by tinging the flag of a green tranf- 
parent colour, inclining to brown, when only a 
little of the metal is fcorified ; but as foon as any 
larger quantity thereof is diflblved in the flag, this 
becomes firfl: a blackifli brown, and afterwards 
quite black and opaque. 
SECT. XLVIL 
Bifmuth is known by its communicating a 
yellowifh brown colour to borax : and Arfenic 
by Its volatility, and garlick fmell. Antimony, 
both in form of regulus and ore, is wholly 
volatile in the fire, when it is not mixed with 
any other metal (except arfenic), and is known 
by its particular fmell ; eafier to be diftinguiflied, 
when once known, than defcribed. When the orsL 
of antimony is melted upon the charcoal, it bub- 
bles conflantly, during its volatiliflng. 
SECT. XLVIL 
Zinc ores are not eafily tried upon the coal 
l(Se(fl:. xxxiii.). But the regulus of zinc, ex- 
pofed to the fire upon the charcoal, burns with 
a beautiful blue flame, and forms itfelf almofl: in- 
ftantly into white flowers, v/hich are the commosji 
flowers of zinc* 
SECT* 
