Boulder-clays, Federated Malay States. 167 



and pebble-bsds point to their being intrusive The first vein I saw 

 was on Kinta Tin Mines Ltd. In 1908 tbe top of this vein was visible 

 and was sketched. In section it conld be seen terminating in a thin 

 stringer of kaolin in 'the red clay. Later on the top was cut away by 

 a monitor and the vein exposed near the limestone. The junction 

 witli the clay is shown in plate x of the old edition, as also another 

 junction between a kaolin-vein and the clay. In vol. Ixviii, 1912, of 

 the Quarterly Journal of the Geological Society, p. 149, fig. 4, a figure 

 is given of a kaolin-vein and a tourmaline-vein on Tekka Ltd. 



The evidence of the form of the veins is strengthened by a case 

 where a kaolin-vein was found to be bordered at its junction with the 

 clay by a mica-tourmaline rock resembling a rock found at the junction 

 of granite and clay on Tekka Ltd. This rock is markedly different 

 from the body of the vein itself and can only be interpreted as the 

 result of metamorphism of the clay. The tourmaline is blue, as on 

 Tekka Ltd. 



Sections of kaolin-veins have been exposed in beds high above the 

 limestone and also in excavations where they can be seen close to 

 limestone. In the latter one may see what I believe to be the effect 

 of the settling-down of the clay, pebble-beds, and kaolin-veins, as the 

 limestone dissolves. It shows itself sometimes as a brecciation at 

 the junction, an excellent example of which was photographed some 

 years ago. In other cases the junction of kaolin-vein and clay is very 

 confused, and pieces of the kaolin are separated from the parent vein. 



Against the evidence of the kaolin-veins must be set the buried 

 trees that are occasionally found. I have explained these as being trees 

 that have fallen into old and forgotten excavations. The sandy 

 casing found round some of them supports this view {vide Q.J.G.S., 

 Ixviii, pp. 150-1, fig. 5, 1912), but a section has lately been photo- 

 graphed, unfortunately too late for illustration ; that is a puzzle I am 

 ■unable to solve. It occurs on the Gopeng Consolidated property. 

 On the right is a very clearly-marked fault with grey pebble-beds 

 and clay on the right of the fault, and the same beds, stained 

 red and disturbed, on the left. To the left of the fault is part of 

 a big kaolin-vein. It looks as though it had been slightly bent by 

 movement of the clay, but can only be regarded as intrusive, since it 

 is the same vein as that mentioned above as being bordered by mi-ca- 

 tourmaline rock. There are masses of kaolin, isolated in section, 

 which may be joined to the parent vein further in, or may be portions 

 sheared off by settling over the limestone. The fault does not touch 

 the main mass of kaolin. Only six feet, or thereabouts, above the 

 kaolin is a mass of wood around which I could find no casing when 

 I saw it some days after it was first uncovered. Here, then, we have 

 a kaolin-vein that has effected alteration of the rock it is intruded 

 into, well-preserved wood 6 feet from it in the same clajr, and a fault 

 that does not help matters one way or the other. 



In an earlier chapter the possibility was touched on of there being 

 in the Kinta Valley detrital deposits belonging to the era when the 

 Peninsula was united to the Archipelago or to that when the former 

 was a gronp of islands. This must be considered briefly in connection 

 with the Gopeng deposits. 



