16 DISTRIBUTION OF MINERALS IN SARAWAK 



able quantities and some in traces; and in addition platinum 

 molybdenum, petroleum, catseyes, and spinel le ruby have been 

 observed. In Sir J. Brooke's " Private Letters" mention is 

 made of a large stone called the " Brooke diamond " which on 

 examination proved to be a white topaz, but the precise locality 

 whence it was obtained is not specified, although we may sur- 

 mise that it was a genuine Sarawak stone. 



I find also in a work on China entitled "The Middle King- 

 dom" (1848) mention of Corundum being imported from Borneo 

 for the use of Chinese lapidaries; no authority, however, is 

 cited for the occurrence of this mineral in Borneo: the note 

 probably refers not to Corundum, properly so called, but to dia- 

 monds, brought from Landak and Sarawak. 



In the above enumeration it is noteworthy that Sarawak Pro- 

 per exhibits all the minerals of which traces have been detected 

 in the other districts, and several others besides. When we con- 

 sider that it is the only portion of the Territory in which a 

 systematic search has been attempted (generally by amateurs) and 

 that there is a close general similarity in geological constitution 

 over the whole of the N. W. coast of Borneo, there is fair 

 ground for conjecture that available deposits of one or more of 

 the above mentioned minerals, will be discovered in some other 

 localities in which traces only have been detected as yet. 



Gold occurs in the form of fine sand, or minute flattened plates 

 in alluvial deposits over a great part of Sarawak. Washings 

 are carried on in Upper Sarawak at Bau, Paku, Grumbang", &c, 

 in Samarahan at Sirin, in Sadong at Malikin, and in the Batang 

 Lupar at Marup. The operations are wholly superficial, al- 

 though at Marup and Bau, the principal Chinese washings in 

 the country, the stratified clays belonging to the Sandstone for- 

 mation, and containing at the latter locality decomposed por- 

 phyritic dykes have been cut into to some extent. The precious 

 metal has never to my knowledge been regularly mined for in 

 Sarawak, nor indeed has it been discovered in situ it its original 

 matrix, except in the case of the gold contained in the vein- 

 stoues and quartz- reefs of the Antimony district, and that asso- 

 ciated with a lode of argentiferous arsenic at Bidi. The 

 alluvium of the limestone caverns and fissures, and especially the 

 sands in the beds of streams have yielded sufficient to induce 

 the natives to work in such spots. The washiug is carried on 

 partly by Malays, who are usually gamblers and work only at in- 

 tervals, but chiefly by country-born Sambas Chinese. Their 

 mode of operation has been fully described by Crawfurd, Hors- 

 field, St. John, and others, and it will therefore be unnecessary 

 to enter into anv details here. 



