108 VOLCANIC AREA OF EAST MORETON, ETC., DISTRICTS, Q., 



Sp. No.61c. Both macroscopically and microscopically like 

 61b. Hence this is also a granulite. 



The knotted specimens 61b, and 61c, were obtained on Mt. 

 Delaney at a lower level than 61a, that is closer to the great 

 granitic intrusive mass which underlies the mountain. The 

 knotted structure is therefore probably the result of contact 

 metamorphism effected by the granite. From the same cause 

 the sagenitic rutile needles developed in the quartz, and the 

 minerals zoisite, cyanite and rutile in the felspar. The develop- 

 ment of topaz may have taken place at the same time. The 

 irregular shape of the quartz and felspar grains in these rocks 

 and the manner in which they occasionally interpenetrate show 

 that the minerals were softened, almost remelted, when the 

 schistosity was produced. The quartzes and felspars are usually 

 squeezed out into long streaky grains. 



Sp, No.60. Greenstone. Loc: Fife's Range on Delaney's Ck. Road. 



i. It is a dark rock occurring in the form of dykes not only on 

 Fife's Range, but also in Wararba Parish, on Black's Hill near 

 Neurum. in. the Delaney's Ck. Valley, and in larger masses on 

 Mt. Mee. It is evidently an altered igneous rock. 



ii. (I) Texture: noncrystalline; even-grained, grain-size medium; 

 fabric, allotriomorphic granular; the adjacent crystals are highly 

 crushed and squeezed into one another by heat and pressure 

 combined. 



(2) Essential minerals : (i.) orthoclase felspar with highly 

 irregular outlines; it is crowded with inclusions, some of which, 

 like the magnetite, are primary, and some, like the zoisite, 

 cyanite, and epidote, are secondary, (ii.) Actinolite, a green 

 fibrous hornblende, highly pleochroic in colours from light straw- 

 yellow to deep bluish-green. In notable and diminutive amount 

 we have (iii.) brownish, slightly titaniferous, magnetite, a great 

 deal of which is secondary ; a few plates of ilmenite also occur. 

 (iv.) Honey-coloured non-pleochroic epidote with high refractive 

 index and double refraction; it is commonly included in felspar. 

 (v.) Very pleochroic chloritoid minerals with a double refraction 



