OCCURRENCE OF QUARTZ IN CEYLON. 173 



most beautiful and striking case, however, has been lately noted at 

 Crystal Hill estate near Matale. In one place where the quartz rock 

 has been thrown into a small low anticline , a regular fine cleavage 

 has been set up radially to the fold, and the quartz has been entirely 

 re- crystallized, becoming glass-clear, and, in places, hypidiomorphic 

 crystals of quartz have been developed, irregularly intergrown with 

 their long axes parallel to the cleavage. This longitudinal inter- 

 growth of the crystals sometimes produces forms approaching " scep- 

 tre quartz," i.e., long crystals bearing at one end a stumpy crystal. 

 A good example of "sceptre quartz" may be seen in the mineral 

 gallery of the Colombo Museum, though the origin of that actual 

 specimen is not known. In the clear quartz are discontinuous 

 faint milky lines at right angles to the cleavage, which represent the 

 partings of the original foliation. I would not suggest that all the 

 idiomorphic and hypidiomorphic quartz crystals found in river 

 gravels, especially in the Ratnapura District, originate from the 

 metamorphism of quartz rock, but it is certainly a mode of origin 

 which has previously been overlooked. 



The passage of granular quartz into homogeneous transparent 

 quartz may also be well observed on the Passara-Madulsima road, 

 where the rocks are thrown into undulations at right angles to the 

 general foliation strike. Here it is the pink or rose quartz that is 

 developed. In places the rock is full of iron ore, probably ilmenite. 

 On examination of a hand specimen with a lens abundant grains 

 of garnets are seen. These show no crystal outline, but appear as 

 pale pink blotches, fading almost insensibly into the surrounding 

 pink quartz. Under the microscope these garnets are seen to be 

 elliptical in section , with their long axes parallel. They show obvious 

 signs of crushing. The quartz is traversed by faint parallel lines 

 or cracks, also parallel to the long axes of the garnets and marked 

 by some pale green decomposition product. These cracks appear to 

 indicate the original grains. Between crossed nicols the whole of 

 the quartz in the slide, except one grain, extinguishes parallel to 

 these cracks and to the garnets, indicating that the quartz has been 

 re-crystallized and oriented in this direction, which would.be the 

 direction normal to that in which the metamorphosing strain 

 occurred. The one grain which is not parallel to the others 

 extinguishes at an angle of 45° with the general direction. 



Under a high power, especially by oblique substage illumination, 

 the quartz is seen to be crowded with rutile needles, of which a large 

 number are parallel, arranged at right angles to the garnet axes. 

 One or two beautifully developed little idiomorphic crystals of 

 rutile are also seen. The colour of rose quartz is usually attributed 

 to the presence of titanium dioxide, and the abundant presence of 

 rutile would confirm the supposition in this case. 



Rose quartz is fairly common in the Island, but seldom seen in situ. 

 When in uncracked pieces of sufficient size it may be cut en cabochon 



