On the Occurrence of Platlna and Diamonds in Borneo. 285 



The diamond mines lie more to the north, but likewise on 

 the west side of the Ratoos Mountains ; there, likewise, a red 

 bed of clay stretches over the surface, 6 to 7 fathoms deep, and 

 there is also a bed, one fathom deep, composed of quartz 

 pebbles, and fragments of syenite and diorite ; more rarely 

 a marl occurs, containing recent shells (fistroia cardium). 

 In this deposit the diamonds are distributed, sometimes ac- 

 companied by magnetic iron sand, by plates of gold and 

 platina, and by small pieces of native iron. The surest sign 

 of the presence of diamonds is the occurrence of small pieces 

 of black quartz, with disseminated iron-pyrites and platina, 

 Avhich are termed Batoe (Batu) Timahan^ or Baloe Farak 

 Jatan, 



A considerable quantity of gold and platina is obtained 

 along with the diamonds. In the districts of Goenong (Gu- 

 nong) Lawak, Tapang, and Oedjong Moerung (Udjong Mu- 

 rong) alone, four thousand workmen are employed in the pro- 

 cess of washing. 



The occurrence of platina in this district was made known 

 in 1831 by Mr Hartmann, then the resident at Banjermas- 

 siug. Hitherto no advantage has been derived from his dis- 

 covery, as the platina is thrown away as entirely useless. It 

 is, however, certain, that a tenth part of platina is washed out 

 with the gold. The produce of Poelo Arij is 1000 tael of 

 gold, and thus 100 tael of platina are obtained ; and if we 

 calculate the produce of the washings of the district in the 

 mountains nearer the equator at four times as much, we have 

 500 tael of platina washed out and cast away. Besides this, 

 there is what is obtained and thrown away on the west coast. 

 According to Cra\\^urd (History of the Indian Archipelago, 

 iii. p. 482), the whole gold obtained in the Chinese colonies 

 of Mandoor and Montrado, on the west coast of Borneo, is 

 about 88,632 ounces, of which the tenth part, or about 8000 

 ounces, or 4000 tael, are platina. We are probably under 

 the mark, when we estimate the annual quantity of platina 

 lost in Borneo at 5000 tael, or 10,000 ounces, that is, 625 

 pounds. (From Foggendorjps Annalen^ 1842, No, 3.) 



