DISTRIBUTION OF MINERALS IN SARAWAK 25 



the Borneo Company to report on the antimony mines, is deci- 

 dedly in favour of the aqueous, as against the igneous theory of 

 the origin of the antimony. 



Quicksilver. The mineral was discovered in situ about seven 

 years ago, by the indefatigable exertions of Messrs. Helms and 

 Walters of the Borneo Company Limited, who prospected over 

 the whole of Sarawak Proper, and ultimately succeeded in track- 

 ing the small fragments of cinnabar that are scattered over the 

 district, to a hill on the right bank of the Staat river, and be- 

 tween it and the Sibugoh mountains. 



During the progress of the exploration, a rough but service- 

 able sketch-map was executed, embracing Sarawak Proper and 

 the Upper Samaraham, on which the positions of the principal 

 deposits of antimony and cinnabar will be found accurately 

 marked. 



The Hill containing the cinnabar — for it is in this form as 

 usual that the quicksilver occurs — is known by the name of Ta- 

 gora, and is, or rather was, a steep twin-peaked mass of semi- 

 metamorphic rock, rising to an elevation of about 800 ft. above 

 the sea-level, in the upper parts of which the ore is found depo- 

 sited capriciously in strains, pockets and strings, with now and 

 again a little metallic mercury. 



The component rocks are argillaceous shales, with sandstones 

 interbedded ; these have been very extensively disturbed and 

 contorted, and the former are as I have said, partially metamor- 

 phosed into an impure state, glittering with cubical iron pyrites^ 

 and, in the higher portion of the hill, full of cutters of carbonate 

 of lime. Nodules of black shale occur here and there in the state 

 which is, in appearance, amygdaloidal, through being often 

 thickly spotted with calc-spar, baryta, and pyrites. Some layers 

 of sandstone which I observed cropping out at a very high angle 

 on one of the peaks, did not seem to have been affected in the 

 same degree with softer shales by the metamorphic action, and 

 still retained their normal structure, though hardened to such a 

 degree as to be most refractory in working. 



The ore is found in the slate, rarely in the sandstone, and, as 

 is the case with all known deposits of Cinnabar, is distributed 

 with great irregularity in the matrix. Hence the yield has 

 proved extremely variable, and at times the ore has seemed to be 

 lost altogether. No such thing as a lode can be said to exist, 

 though short strings are met with. One of these attained a face 

 of six inch.es, and was traced down to a depth of mafny fathoms. 



