[meteorite-list] TSCHERMAK G. (1885) - Part 4

From: bernd.pauli_at_paulinet.de <bernd.pauli_at_meteoritecentral.com>
Date: Thu Apr 22 10:32:49 2004
Message-ID: <DIIE.0000002300001BD5_at_paulinet.de>

TSCHERMAK G. (1885) Die mikroskopische Beschaffenheit der Meteoriten
(Stuttgart E. Schweizerbart'sche Verlagshandlung, E. Koch, 23 pp.).

English Translation: The Microscopic Properties of Meteorites, Vol. 4,
No. 6 (Smithsonian Contributions to Astrophysics, Washington, D.C., 1964).

Translation by J.A. Wood and E.M. Wood

General Characteristics of Meteorites


The chondritic texture is peculiar to meteorites; it is not found in terrestrial rocks.
The spherulites in some obsidians and perlites are silicate spheres, but the fibers
they contain radiate from their centers, while those in fibrous chondrules radiate
from eccentrically located points.

Some stones contain black veins, whose filling is identical with the black ground-
masses of the breccias described earlier. The walls of the cracks sometimes appear
displaced relative to one another. The stones often tend to break along these veins;
the surfaces then exposed are streaked and metallic in lustre (Pultusk, Mocs, Molina).

The tuffaceous meteorites are finely porous and absorb fluids readily. Most meteorite
stones, however, behave as if they had been baked or sintered; they ring like brick when
struck. Large voids or pores, as in Richmond, are rarely seen. Walls of the druses in Juvinas
contain euhedral crystals. In both cases, one has the impression that the spaces were
produced during a secondary heating of the stone.
Received on Sat 13 Mar 2004 04:00:03 PM PST