Note 4 — Chapter VII · CENTRAL CHILE:—STRUCTURE OF THE CORDILLERA.
Reading edition
This mineral is extremely common in all the formations of Chile; in the gneiss near Valparaiso and in the granitic veins crossing it, in the injected greenstone crowning the C. of Quillota, in some granitic porphyries, in the porphyritic conglomerate, and in the feldspathic clay-slates.