190 SARAWAK AilXERALS.--.BY J. S. GKIK'JE. 
in so many of the Gold and Antimony ores is most 
objectionable from the metallurgist’s point of view. 
Antimony .—Specimens of metallic Antimony have 
been found in most of the metaliferous deposits of 
Upper Sarawak, but only in the Limestone hills near 
Busau has it occurred in any quantity. Here it is 
found in masses, some of considerable size, lying in 
fissures in the limestone and also in the Alluvium round 
the foot of the hills. At no time has its production 
formed more than a mere fraction of the out-put of 
Sarawak Antimony. 
Gold .—Gold is and has been for some years the chief 
metal export of the country, practically the wdiole 
amount having been derived from the Bau and Bidi gold 
mines in Upper Saraw r ak ; the native alluvial washings 
produce only a small and very uncertain quantity. 
The metal has a wide distribution, having been found 
in the Rejang at Sariki, in the Batang Lupar at Marup, 
in the Sadong at Melikin and elsewhere, in the Samara - 
han at Sirin, and practically all over Sarawak Proper. 
Most of these deposits are however only low grade 
alluvials of no extent. 
At Bau and Bidi gold occurs in a series of Marls and 
Shales pierced by numerous dykes, the rocks in the 
auriferous zone being brecciated, much altered, and 
silicified, and retaining but little trace of their original 
form. These masses of altered rock are found to ex¬ 
tend along a series of fault lines and there is little 
doubt that the origin of the gold is closely connected 
with the presence of the dykes and these faults. 
The gold which is alloyed with some 20 per cent of 
silver is in an extremely fine state of division, being 
rarely visible ; what coarse gold there is occurs in thin 
leaves and plates. Along with the gold are found 
Arsenic, Antimony, Stibnite pyrites, Realgar etc. 
Silver .—Only occurs alloyed with gold. 
Mercury .—Small quantities of Mercury were observed 
from time to time while working the Tegora Cinnabar 
deposit. 
Sulphides, etc. 
Realgar. . -Of frequent occurrence in the gold bearing 
shales of Bau and Bidi, generally as small crystals 
