﻿156 SMITH. 



Norte we find them in a narrow, irregular belt bordering the granite 

 (f. n.) dike which runs roughly north and south across the country. 



At Dalumat I found magnetite, talc, mica (several species), actinolite 

 and chlorite schists, all in a very much disturbed and mixed condition, 

 but in this region the mica and talc schists prevail; farther to the 

 north near Dungn-Dungon, magnetite schists are better developed, and 

 there is also a very feeble development of eclogite. I found, from my 

 study of schists and eclogites from the Coast Eanges of California, 

 that the metamorphism of sedimentary rocks usually produced gneisses 

 and schists, whereas the eclogites could in some cases at least be traced 

 back to an igneous antecedent. However, in the Iloeos Norte region I 

 have not in mind a single instance where I could actually trace these 

 transformations in the field. This much, and only this, we can be sure 

 of at the present time; that is, that the mica and talc schists are found 

 between the granite (f. n.) intrusive mass and the later sediments; 

 the magnetite schists and eclogites are more intimately associated in 

 the field with the basal igneous mass, usually near its edges. 



MINERALS OF THE SCHISTS. 



Actinolite schists. — These are to be found in patches everywhere border- 

 ing the serpentine area. Some of the rocks are entirely made up of long 

 actinolite crystals, while in others actinolite is only one of the several 

 constituents. SlidesJrom two different rocks from near Pine View Point 

 were examined. The first one consists largely of a mass of actinolite 

 fragments with interstitial, more or less rounded feldspar grains, rarely 

 showing polysynthetic twinning, the whole complex with every appearance 

 of having been derived from a sediment; extreme granulation is a fea- 

 ture of this rock. The second one is made up almost entirely of actin- 

 olite with probably some interstitial chlorite. In parallel, polarized 

 light the actinolite shows marked dichroism. a = colorless. c = olive 

 green. The actinolite does not occur in whole, unbroken crystal sec- 

 tions, but is in a very much frayed state, in fibers which are the result of 

 breaking along the cleavage lines parallel to c. 



Mica and micaceous schists. — Nearly every species of mica known to 

 mineralogy can be found, it seems, in the schistose areas near Pasuquin. 

 These minerals all occur in small pieces, seldom as complete crystals, 

 they occur very irregularly along shearing planes. The lighter micas such 

 as muscovite, paragonite, etc., and micaceous talc seem to predominate. 



In the cut which Mr. Burdette has put into the side of the hill at 

 Dalumat, I saw pockets of nearly all species of mica, but always in 

 a more or less comminuted condition. These micas could very possibly 

 be manufactured into lubricants and paints. One green, chlorite variety 

 should find some use as a paint in these Islands, particulary in decorating 

 the frames of the numerous cheap pictures of saints, etc., which the 

 Chinese sell to the natives. According to "Mineral Industry" for 1905, 



