X, A, 1 Smith, Edding field, Fanning: Philippine Minerals 83 



can be seen in the Santo Tomas Museum. When perfect it is 

 used as a gem. There is no production in the Philippine Islands. 



Analcite— NaAl (SiOg) 2+H2O. 



This mineral occurs as an alteration product of leucite in 

 some volcanic rocks of limited distribution in Masbate. 



Andesine. (See Plagioclase). 

 Anorthite. (See Plagioclase). 

 Anthophyllite— (Mg, Fe)Si03. 



This mineral is a variety of amphibole in long dirty white to 

 brownish fibers, and is associated with serpentine and asbes- 

 tos. It occurs in Ilocos Norte. In some cases it could be used 

 as a substitute for asbestos. There is no production in the 

 Philippines. 



Apatite— Cas (CI, F) (POJ 3. 



Apatite occurs as large yellowish crystals in small amounts 

 in metamorphic rocks near Pasuquin, Ilocos Norte, and also in 

 minute crystals in many igneous rocks in the Philippine Islands. 

 It is valuable for fertilizer if found in large enough quantities. 

 There is no production in the Philippines. 



Aragonite — CaCOg. 



The mineral is found so far in one locality, Talim Island, La- 

 guna, in long clear crystals in vugs in basalt. It has no economic 

 value. 



Arsenic — As (metallic) . 



This mineral is deposited presumably from hot springs in the 

 form of kidneys (reniform) . It is found near Buguias, Moun- 

 tain Province. There is no local use for arsenic. 



Asbestos— H,(Mg, Fe)3SiA- (?) 



Asbestos is associated with serpentine in Ilocos Norte. No 

 first-grade asbestos has yet been found. It consists practically 

 of longitudinal fibers. One small sample of cross fiber (see 

 Chrysotile) is in our collection. There is no production in the 

 Philippines. 



Asphaltum — Complex series of hydrocarbons. 



One small specimen was brought in from the Eastern Cordil- 

 lera, Luzon, which is of doubtful authenticity. 



Augite— (Mg, Fe) (Al, Fe)2SiO«. 



This mineral is one of the pyroxene group of silicates — common 

 as a rock mineral. Augite has no economic value at present. 



