﻿part 3] STANNIFEROUS DEPOSITS OE KINTA DISTRICT. 169 



masses are composed of phyllites, indurated shales, and some 

 quartzite bands, and in places bear great resemblance to the area 

 previously described. 



Standing out in isolated grandeur above the general level of the 

 valley, and forming very striking natural features, are numerous 

 limestone cliffs with bare light-coloured faces which immediately 

 arrest attention. They are most numerous in the north-western 

 part of the valley, but the biggest mass of all is half way between 

 Gropeng and Kampar ; it is more than 4 miles long. 



As previously noted, the bed-rock underlying the tin-ore deposits 

 has proved, in a large number of mines in various parts of the 

 valley, to be a metamorphosed limestone, and to have a very irre- 

 gular surface. It is the custom in Malaya to refer to the 

 prominences in this irregular floor as pinnacles, and to the masses 

 standing above the level of the valley as cliffs or hills. That 

 nomenclature will be followed in this paper. 



TIL GrEOLOGTCAL HlSTORY OE THE KlNTA VALLEY. 



Fossils are practically absent in the metamorphosed limestone of 

 this valley; but at Changkat Pari, near Tpoh, Mr. Scrivenor 1 

 found great numbers of what were ' probably once crinoid-stems 

 and other organisms.' These, however, proved to have ' no homo- 

 taxial value.' On the other side of the Main Ridge he found 

 ' the same limestone, but less altered and containing recognizable 

 fossils.' These having been examined, Mr. Scrivenor arrived at the 

 conclusion that the most that could be said was that the limestone 

 was Carboniferous, and that it was the oldest rock known in situ 

 in the Federated Malay States. 



Lying immediately upon the metamorphosed limestone are the 

 so-called ' Gondwana Rocks,' and above them are the recent 

 deposits. 



The granite of the Main Range on the east of the* Kin ta Valley, 

 of the Kledang Range on the west, and of the neighbouring out- 

 crops, is a pale porphyritic granite of an acid type. It contains 

 tourmaline and muscovite in abundance, and frequently carries 

 tin-ore. From the petrological, mineralogical, and geological 

 points of view the granite in all the outcrops of the Kinta Valley 

 seems to be of the same age, which must be later than that of 

 the limestone that has been metamorphosed by it. For several 

 reasons Mr. Scrivenor has come to the conclusion that it is a 

 Mesozoic granite and probably Cretaceous. 



Taking the limestone, then, as Carboniferous or Permo- 

 Carboniferous, and the granite as Mesozoic, we have the following 

 sequence in the Kinta district : — 



1 J. B. Scrivenor, ' The Geology & Mining Industry of the Kinta District ' 

 1913, p. 22. 



