can be no doubt that Diamonds are very widely distributed in the island
of Borneo. Dr. Theodor Posewitz, a mining engineer, who resided there
for nearly three years, published in Berlin, in 1889, a valuable work,
in which he discusses at great length the mineral resources of Borneo,
and gives an interesting description of the occurrence and production
of Diamonds. Much has also been written on the subject in the reports
of the Mining Department of the Dutch East Indies.
Diamond-fields exist in the rich gold-bearing district of Tanahlaut,
especially near Martapura> in the south-east of Borneo. Kusan, in
the east of the island, is also a district of much repute for both
Diamonds and gold. But, perhaps, the most famous locality is Landak, in
Western Borneo. Landak is situated a few miles E.N.E. of Pontianak, the
capital of Dutch Borneo, and is about three day's steam from Singapore.
Sangan, also in the west, likewise yields Diamonds, especially in the
rivers Sikajam and Meran. Finally, the Sarawak River has, of late years
been cited as a Diamond yielding stream, and some very fine Diamonds,
both white and of rare fancy colours, have been found there ; but the
deposits can be worked for only a few months in the year.