ON SOME TIN-DEPOSITS OF THE MALAYAN PENINSULA. 229 
17. On some 'Tin-pEpostrs of the Matayan Payinsuta. By Patrick 
Doyrx, Hsq., C.K. (Read January 8, 1879.) 
[Communicated by Rey. T. Wiursnire, M.A., F.G.8.] 
TueEre is a striking resemblance in the mineral characteristics of all 
parts of the Malayan Peninsula, especially in regard to the mode of 
occurrence of the deposits of tin-ore (cassiterite). 
The Malayan tin-field, including the islands of Banca and Billeton, 
extends over 17 degrees of latitude and 10 of longitude; but the 
observations of Messrs. J.ogan, Horsfield, and others, in different 
parts of this area, correspond with those which haye been noted in 
Larnt. The peninsula consists of granitic rock overlain generally by 
sandstone, and frequently also by laterite or cellular clay-ironstone, 
and, tothe north, by hmestone. A granitic mountain-range extends 
along the whole length of the peninsula, on both sides of which, 
but especially on the western or Sumatran one, are extensive alluvial 
plains, but little above the level of the sea. Iron, tin, and gold are 
the principal metals. Ores of the first are found everywhere; and tin 
has hitherto been found in all parts where search has been made. 
Perak is the second Malay State on the west side of the peninsula, 
counting from the north ; and Larnt, its chief province, is an irregular 
strip of land about 70 miles long and varying from 10 to 25 miles 
broad, bordering the coast. 
Larnt, for some ten miles inland from the sea, is a level plain ; 
then the mountain-ranges begin and rise to a height of nearly 5000 
feet, running in an almost unbroken line in a northerly direction, 
with detached hills at intervals at their base. All the land at the 
foot of these ranges is more or less stanniferous. This strip is in 
length above 50 miles, with an average breadth of six. Its level is 
even now being altered by the alluvium brought down from the hills 
by a rainfall which exceeds 150 inches per annum. 
All the ore worked up to the present time has been found in the 
alluvium derived from the mountain-ranges, ¢. ¢., in mining language, 
in stream-works. The ore has been traced up to veins in the rock, 
but these have not hitherto been worked. 
The tin-beds are composed of the débris of granitic rocks mixed 
with the ore; the latter varies in size from particles like fine sand 
to fragments as large as a hazel-nut, the deposit becoming coarser as 
the mountains are approached *. 
* The following specimens were presented in illustration of this paper: 
(1) Fine Tin-sand, obtained from the alluvial flats between the coast and tho 
mountain-range—Larnt, Perak, Malayan Peninsula. (2) Coarse Tin-sand, 
found in alluvial deposits in the interior, beyond the mountain-range and from 
thirty to forty miles from the coast—Kinta, Perak. (3) Yin-gravel, found 
under boulders at varying altitudes of from 5U0 feet to 1500 feet above sea-level 
on the western slopes of the mountain-range—Larnt, Perak. (4) Tin-ore in its 
matrix, obtained from “pockets” of the hills at an elevation of 2000 feet— 
Larnt, Perak. (5) The Yin-tray, which holds the specimens, is made of the 
tin obtained from the smelting of the above ores, and manufactured in Larnt. 
Q.J.G.8. No. 138. R 
