64 MIDDLEMTSS : THE GEOLOGY OF IDAR STATE. 



entirely ringed round, with the exception of the opening of the 

 Meshva river at Bakrol, by the winding and irregular hills of Delhi 

 Quartette. The rocks exposed embrace mica-schist, hornblende 

 and chlorite-schist, gneiss or gneissose granite, grey crystalline 

 limestone, coarse pegmatite, ancient trap dykes, and a peculiar 

 band of coarse white pyroxene rock with tremolite and other minerals. 



The mica-schist is thinly foliated and soft owing to the lar^e 



amount of mica. This is sometimes muscovite 



ac £ aml ° thcr and biotite, as in the Meshva river near 



Bamanvada, where the schists are interca- 

 lated every yard or so with very prominent translucent quartz 

 bands which are as much as 2 to 3 feet thick. At other places the 

 only mica is muscovite (sericite) developed richly or more sparingly 

 in the well-foliated rock, as in specimen No. 29^ (12354, Pi. 11, fig. 4), 

 near Samalpar, Ij miles S.W. of Samlaji. This specimen also contains 

 a little chlorite and rather large grains of tourmaline and iron- 

 ore (magnetite), a very little apatite, quartz with many minute 

 fluid inclusions, and no felspar. Muscovite and biotite-schists are 

 also seen at other scattered places such as Abharpur, Pala (Palo), 

 (4V4)' Gadadar, ( 4 \%, 12373), and at many points along the tribu- 

 tary of the Meshva between Meru and Bamanvada.— as g& from 

 Sunak. At many places, however, this rock is intercalated with 

 veins of more felspathic gneissic material in varying proportion 

 till it passes into the gneiss or well -foliated granite seen typically 

 at Vandiol and Jesangpur. This will be described presently. These 

 scattered outcrops of schist and gneiss indicate very extensive, 

 and doubtless very thick, rock-masses totalling many hundreds 

 and possibly thousands of feet. Chlorite and sericite-schist ( 2 (J 

 12355) is found close up against the Delhi Quartzite at Khercha 

 (Kherancha). 



Other schists are the hornblende-schist of Vijapar (/ 9 6 , 12356), 

 a finely foliated rock containing minute blades of green hornblende 

 and numerous irregular grains of epidote or (?) clinozoisite in a 

 vague crushed ground-mass of quartz or quartz-felspar. It is pro- 

 bably an epidiorite. Another complex crystalline schist, found near 

 the latter up the small tributary stream, is banded with flesh-red 

 quartzo-felspathic (with microcline) layers so as to constitute a 

 mixed gneiss, of which the dark green layers contain chlorite, 

 white mica, epidote, some calcite and a little sphene (4^, 12362). 

 The rock is also penetrated by much altered ancient dyke-like 



