34 HISTORY OF THE GEMS FOUND IN NORTH CAROLINA.
muscovite
mica, that are green when viewed through the side of the prism, and of
green chlorite, from several other localities in Alexander County.
A
remarkable specimen of this kind, that was a " nine-days wonder " some
years ago, was the so-called Gibsonville emerald. This was a stone
weighing 9 ounces, plowed up near Gibsonville, Guilford County, which
was pronounced a genuine emerald by some local expert, who tested it,
and with the microscope showed that it contained various small
diamonds. Its value was estimated up in the thousands, and $1000 was
reported to have been refused for it by its owner, who, as it was
believed to be the largest known emerald, expected that it would bring
him a fortune. Being, therefore, too valuable to be be entrusted to an
express company, he put himself to the expense of a trip to New York,
where his prize proved on examination to be a greenish quartz crystal,
filled with long hair like crystals of green byssolite or actinolite,
on which were series and strings of small liquid-cavities that,
glistening in the sun, had led to the included diamond theory. The best
offer that he received for the stone was $5.
Fluid Inclusions.—In
March, 1882, Mr. William E. Hidden described and illustrated before the
New York Academy of Sciences some unparalleled specimens obtained at
Stony Point, Alexander County—the emerald locality elsewhere noted.8
Here some 400 pounds of choice large crystals of smoky quartz were
taken out of a " pocket" in a quartz vein, besides much of less fine
quality. These crystals were filled with cavities containing a clear
lustrous fluid, and of extraordinary size, those of an inch long being
not uncommon, and some of double that length. The largest was 2-1/2 inches by 1/4 of
an inch. So abundant were they that at times the crystals seemed to be
made up of thin walls of quartz, separating a multitude of elongated
cavities, parallel to the rhombohedral or prismatic faces of the
crystals (PL VIII, B).
It
is a matter of great regret that such unique specimens could not have
been studied with the minute care given by Professors Dana and Penfield
to those of Branchville, Conn. But now comes the singular conclusion of
this account. The whole body of these crystals, carefully taken out and
put aside as great 'treasures, were shattered into fragments in a
single night, by the temperature falling below the freezing point. The
contained fluid was evidently, as in the Branchville quartz,
principally water, and its expansion in freezing destroyed the entire
body of specimens. Those with few cavities exploded with sharp
reports, and pieces were blown as much as 15 feet away. Those filled
with small cavities were
