'Euphotide' and serpentine, containing sometimes crystald of augite and
uralite instead of diallage, are thus nearly allied to another more
frequent, and I might almost say, more 'energetic' eruptive rock -- augitic
porphyry.*
[footnote] *In the southern and Bashkirian portion of the Ural. Rose,
'Reise', bd. ii., s. 171.
'Melaphyre', augitic, uralitic, and oligoklastic porphyries. To the
last-named species belongs the genuine 'verd-antique', so celebrated in the
arts.
'Basalt', containing olivine and constituents which gelatinize in acids;
phonolithe (porphyritic slate), trachyte, and colerite; the first of these
rocks is only paartially, and the second always, divided into thin laminae,
which give them an appearance of stratification when extended over a large
space. Mesotype and nepheline constitute, according to Girard, an important
part in the composition and internal texture of basalt. The nepheline
contained in basalt reminds the geognosist both of the miascite of the Ilmen
Mountains in the Ural,* which has been confounded with granite, and
sometimes contains zirconium, and of the pyroxenic nepheline discovered by
Gumprecht near Lobau and Chemnitz.
[footnote] *G. Rose, 'Reise nach dem Ural', bd. ii., s.
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