half an inch in diameter, but as thin as leaf
gold, on a cellular gypfeous matrix, with
native fulphur.
Barytes having a plumofe appearance,
when covered with tranfparent cryftals of
fluor. Barytes in fluor forms a pretty variety.
Barytes has lately been found confu-
fedly cryftallized, of a Iky fdue colour;
the fradture foliated.
But what the chymills call carbonates
of lime, and mineralogifts calcareous fpar,
&c. afford an amazing variety of colours
and cryftallizations, This fubftance is apt
to be confounded with fluor, from which
it efientiaily differs;, the fluoric acid being
of a peculiar nature, and very different from
the carbonic, not to mention other diftinc-
tions. The calcareous fpar here appears in
its moft ufual fhape of the rhomb, and its
modifications, macles, 6cc.
The
The primitive rhomb is rarely found. It
is generally on a dark bituminous limeftone
with pearl fpar and felenite: the primitive
rhomb palling into a variety of modifications.
Lenticular cryftals, on dark limeftone,
blende, &c.
The dogs tooth fpar, forming double
hexagonal pyramids, joined at the bafts.
Hexagonal cryftals of calcareous fpar,
rarely terminating with pyramids of the
primitive rhomb.
Hexagonal cryftals terminating with the
primitive rhomb truncated.
Hexagonal cryftals terminating with the
lenticular pyramid.
Hexagonal cryftals with a variety of terminations
forming pyramids, with three,
fix, twelve, fifteen, and more facets.
Hexagonal prifms of a high topaz colour,
with various terminations.
Fibrous,