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Beryl Mine of Paddioor^ and Geognostic Position of this Gem, 

 in Coimhatoor^ Southern India. By Lieutenant Newbold, 

 Madras Army, A. D. C. to Brigadier-General Wilson, C. B. 

 Communicated by the Author. 



The Beryl mine of Paddioor, or Patialey as it is sometimes 

 termed, is situated at the eastern extremity of a village of the 

 same name, in the Kanghyum Taluk, in the Coimbatoor CoUec- 

 torate, about forty miles E.N.E. from the town of Coimbatoor, 

 which lies in Lat. 11° N., and Long. 77° V E. The surrounding 

 country is an undulating plain, studded with a few short clusters 

 of hills, principally of gneiss and quartz rock. The surface of the 

 plain is intersected by a few ravines and rivulets, flowing to- 

 wards the Noel river, which, rising in the Nilgherry Chain, pur- 

 sues an easterly course to the Canvery. The latter river flows 

 through the midst of this great plain, which is bounded by the 

 Nilgherries to the west, and the Shevaroy and Salem Moun- 

 tains to the east. All these ranges consist of normal rocks, prin- 

 cipally gneiss, hornblende-slate, and mica-slate, associated with 

 granite, greenstone, and basalt in dykes. The rocks that occur 

 in the plain are of a similar description, with beds of quartz 

 distinctly stratified, sometimes highly ferruginous, and passing 

 into garnet rock. Garnets, regularly crystallized, often occur 

 in the gneiss and hornblende slate. Primitive crystalline 

 limestone and a talcose rock occur, though rarely, interstrati- 

 fied with the gneiss and hornblende slate. A remarkable fea- 

 ture is the prevalence of basaltic dykes, accompanied by large 

 travertine and tufa-like deposits of carbonate of lime. The 

 influence exerted by these dykes over crystalline and metalli- 

 ferous developments in these districts is interesting and instruc- 

 tive. Dykes, or veins, of a porphyritic granite too, traverse 

 the gneiss in various directions. The larger veins are gene- 

 rally from W. to E., varying a few degrees to the S. of E. The 

 metallic ores and minerals found associated with these rocks 

 are chiefly the magnetic or black iron ore, disseminated and 

 interstratified with quartz rock in a state of great purity. It 

 sometimes occurs in octahedral crystals, with a whitish mica- 

 ceous looking endail. Both varieties are often highly magnetic 



