A large part of one end
of this bed still remains, and, by careful cutting, fine masses may be
obtained. This bed may be readily found; it is nearly horizontal, and in
its center about four feet from the floor of the tunnel, and about half
an inch thick. It is down Shaft No. 2, on the north wall, and commences
about eighty feet from the shaft. It is cut into in some places, but
there is plenty more left, and can be obtained by cutting the rock
above it and easing it out by means of the blade of a knife or similar
instrument. This natrolite is a grouping of very small but perfect
crystals, having the forms shown in Fig. 5; they are from a quarter to
an inch long, and, if not perfectly transparent, are of a pure white
color; they may be readily recognized by their form, and occurring in
this bed. Its hardness, which is seldom to be ascertained owing to the
delicacy of the crystals, is about 5, and the specific gravity 2.2.
This is readily found, but is no distinction; its reaction before the
blowpipe, however, is characteristic, it readily fusing to a transparent
globule, clear and glassy, and by forming a jelly when heated with
acids. The bed holding the upright crystals is also natrolite in
confused matted masses. This mineral has also been found in other parts
of the shaft, but only in small druses. There is a prospect at present
that another bed will be uncovered soon, and some more fine specimens to
be easily obtained.
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