What does "Tourmaline" mean?
L. They say it is Ceylanese, and I don't know Ceylanese, but we
may always be thankful for a graceful word, whatever it means
MARY. And what is it made of?
L. A little of everything there's always flint and clay, and
magnesia in it, and the black is iron, according to its fancy, and
there's boracic acid if you know what that is and if you don't, I
cannot tell you today, and it doesn't signify and there's potash,
and soda, and, on the whole, the chemistry of it is more like a
mediaeval doctor's prescription, than the making of a respectable
mineral but it may, perhaps, be owing to the strange complexity of
its make, that it has a notable habit which makes it, to me one of
the most interesting of minerals. You see these two crystals are
broken right across, in many places, just as if they had been
shafts of black marble fallen from a ruinous temple, and here they
lie, imbedded in white quartz, fragment succeeding fragment
keeping the line of the original crystal, while the quartz fills
up the intervening spaces Now tourmaline has a trick of doing
this, more than any other mineral I know here is another bit which
I picked up on the glacier of Macugnaga; it is broken, like a
pillar built of very flat broad stones, into about thirty joints,
and all these are heaved and warped away from each other sideways,
almost into a line of steps, and then all is tilled up with quartz
paste.
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