478 ADAMS AND PRATT. 



in the Bureau of Science librai7. The copper has a roughened, some- 

 times crystalline appearance as if it had been deposited in the placer 

 ground and certaia of the miners in the district think that it has been 

 precipitated from solution on the iron in the placer.'' There is more 

 or less copper associated with the other sulphides in the veins of the 

 Paracale district. Near Talcauayan Bay on the head of Eagay Gulf, 

 float copper ore has been found which consists largely of carbonates. 

 Copper ore is said to occur near Sipaco on Caramuan Peninsula. 



Lead and zinc. — A number of the veins in the Paracale district carry 

 some galena and sphalerite together with other sulphides. Such ores 

 probably are refractory. • 



Mercury. — Small quantities of mercury are reported to have been col- 

 lected in the crater of Isarog Volcano. It is found in depressions in the 

 rocks along the stream courses. No cinnabar lias been found. 



Coal. — The East Batan Coal Company has developed a mine near the 

 harrio of Batan on Batan Island. The coal bed is 1.7 meters thick and 

 dips to the north at an angle of 13° from the horizontal. The roof of 

 the coal is a shale which does not stand well, and when drawn to make the 

 entries 2 meters high, heavy timbering is required. The coal is sub- 

 bituminous, similar to the other coals of the Philippines. 



The United States Army has a coal land reservation which includes 

 the west end of Batan Island. The mine openings are near Liguan, 

 where a pier has been built to facilitate the loading of coal. Mining 

 was begun in 1907 and a considerable amount of equipment has been 

 installed gradually. The coal on the west end of Batan Island is of 

 better quality than on the east end, but where opened it is squeezed and 

 faulted to such an extent that none of the workings made on the various 

 outcrops have thus far developed into a successful mine. 



Some prospecting has been carried on at Gatbo where a mine was 

 worked under the Spanish regime, and the deposits on Eapu-Eapu and 

 Catanduanes Islands have been investigated, biit no mining operations 

 are in progress outside of Batan Island. 



Petroleum. — The occurrence of petroleum in Tayabas Peninsula has 

 been discussed under the geology of the Eastern Cordillera. This is 

 the only part of southeastern Luzon from which authentic reports of 

 the occurrence of petroleum have come. 



Stone. — Formerly a considerable amount of stone was dressed and 

 used locally in constructing buildings and bridges and some of it was 

 shipped as ballast in sailing vessels to points where no stone was avail- 

 able. Volcanic tuff was brought from Manila and also some granite 

 which came from Hongkong. Stone is now used only for surfacing 



^Rinne thought that the metallic copper had been reduced by organic matter 

 in the placer. The shape of some of tlie copper specimens siiggests plant forms. 



