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Humboldt, Alexander von, 1769-1859

"COSMOS: A Sketch of the Physical Description of the Universe, Vol. 1"

*

[footnote] *Mitscherlich, 'Ueber die kunstliche Darstellung der
Mineralien', in the 'Abhandl. der Akademie der Wiss. zu Berlin', 1822-3, s.
25-41.

In all these operations, the same affinities manifest themselves which
determine chemical combinations both in our laboratories and in the interior
of the earth. The most considerable part of
p 268
the simple minerals which characterize the more generally diffused Plutonic
and erupted rocks, as well as those on which they have exercised a
metamorphic action, have been produced in a crystalline state, and with
perfect identify, in artificial mineral products. We must, however,
distinguish here between the scoriae accidentally formed, and those which
have been designedly produced by chemists. To the former belong feldspar,
mica, augite, olivine, hornblende, crystallized oxyd of iron, magnetic iron
in octahedral crystals, and metallis titanium;* to the latter, garnets,
idocrase, rubies (equal in hardness to those found in the East), olivine,
and augite.**

[footnote] *In scoriae crystals of feldspar have been discovered by Heine
in the refuse of a furnace for copper fusing, near Sangerhausen, and
analyzed by Kersten (Poggend., 'Annalen', bd. xxxiii., s. 337); crystals of
augite in scoriae at Sahle (Mitscherlich, in the 'Abhandl.


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