﻿ASBESTOS AND MANGANESE DEPOSITS. 169 



Another fibrous mineral which is common in the Ilocos Norte region is 

 an asbestiform actinolite. The analysis shows a considerable percentage 

 of lime. The cleavage across the long axis of the fiber would certainly 

 militate against it in spinning. 



Analysis of asbestiform actinolite" (Ilocos Norte). 



Per cent. 



SiO, 57.50 



ALA .87 



Fe,0 : , .33 



FeO 1.50 



MgO 23.80 



CaO 11.42 



NaX) .75 



KX> .00 



HX) .20 



Lose on ignition 2.98 



99.41 



Plate XI, fig. 14, is a photograph of a specimen of Ilocos Norte 

 chrysotile. 



Field relations. — In the field there are two noteworthy forms of occur- 

 rence. One is the formation of parallel fiber in the Dalumat and Baruyen 

 schist areas, and the other is the "pocket" formation on the Dungn- 

 Dungan estate; that on the Tug-a-tug promises to be very much the 

 same as that of the Dungn-Dungan. The Dalumat and Baruyen asbestos 

 is confined almost entirely to shear zones, and hence is of local and 

 limited occurrence. 



A rather large pocket of inferior asbestos consisting largely of tremolite 

 and talc was struck in the shaft in the estero, tributary to the Baruyen, 

 but there are also several small veins of "cross fiber" material of good 

 appearance which makes it more than likely that if this locality were 

 diligently worked, some good results would be obtained. Below is a cut 

 showing the appearance of the workings at this place. (PL IX, fig. 15.) 



Chrysotile or fibrous serpentine is the principal product of the Canadian 

 mines and its characteristic occurrence in that region is as a fine fiber. 

 usually not over 1 centimeter in length, running crosswise from wall to 

 wall of the vein. The serpentine in the Canadian mines is penetrated in 

 every direction by innumerable, narrow veins filled with this fibrous ser- 

 pentine. Occasionally, this fiber attains a length of 17 centimeters. 



It is my opinion that the mining and dressing operations will be much 

 the same in the Ilocos region as in Quebec; that is, the whole containing 

 rock will be mined, crushed in rotary crushers, run through a "cyclone 

 blower," and dried in rotary kilns. 



17 Analysis by L. A. Salinger, Chemical Division, Bureau of Science. 



