$2 MIDDLEMISS: GEOLOGY OF HAZARA AND BLACK MOUNTAIN. 



and sometimes massive. Nos. Ts ?^- to ——, inclusive, illustrate this 

 series and are apparently all connected genetically with one another. 

 They all possess a highly crystalline-granular structure, and are 

 composed in different ways of plagioclase, augite, hornblende, garnet, 

 rutile, iron-oxide, and secondary epidote and quartz. Most of them 

 contain felspar, and this is altered almost completely to a dead- 

 white saussuritic material, dull and opaque in transmitted light, and 

 o-iving scarcely any colour phenomena between crossed nicols. In 

 _j_ especially, and also in many others, e.g., gf^ to F | 5 clear colour- 

 less epidote is intergrown with vermicular quartz and appears to 

 have arisen from the decomposition of the felspars, among which 

 it lies in irregular ragged ophitic masses. Deep amber-coloured 

 rutile granules are fairly characteristic. The augite is green, and is 

 found associated in close granular connection with the garnets, 

 which are very common. This connection is very noticeable in -g| 4 -, 

 where the mineral, by analogy presumably augite, possesses none 

 of the ordinary characteristic cleavages of that mineral, but only 

 irregular cracks, as if it were mimicking the associated garnets. In 

 | 5 again, where the same association of the two minerals is seen 

 there are good examples of augite shewing characteristic cleavages. 

 g | 5 also contains bundles of picrolite. Hornblende in this series of 

 rocks ( gf 2 to yfo ) is ver y common, being present in nearly all the 

 slides. It occurs in beautifully preserved short prisms, perfectly 

 fresh-looking, with cleavages fine and distinct. Its colours are gene- 

 rally deep and bright, and the pleochroism very pronounced. In 

 -g|_ the hornblende is present in smaller grains, and there is a good 

 deal of quartz also present. In ¥ | 5 the hornblende appears to have 

 arisen from the augite by uralitization, as it keeps the same ophitic 

 shapes as the augite. In F | T the hornblende has a marked tendency 

 to be drawn out and to lie parallel to the lenticular -tabular quartz- 

 felspar layers. In another boulder, ¥ § y (see plate II, fig. 7), the 

 hornblende with garnet, rutile, and iron ore make up the whole 

 of the rock ; and this seems to have its complement in ¥ |g, which is 

 made up entirely of crushed felspar and quartz, the former as usual 



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