1917.] 



Limburgite in British Baluchistan. 



295 



lava, while the presence of olivine and of augite as phenocrysts 



limburgit 



The number of the com- 



plete analyses of limburgite available for study and comparison 

 is rather "small, and these show that there is a considerable 

 variation in the composition of the different examples of limbur- 

 gite, the percentage of SiO, lying between 46-76 • and 38*34.* 

 The Hamandun specimen is exceptionally rich in Al ' ) 8 , fairly 

 rich in CaO, and may be compared with the limburgites the 



Baluchistan 



given below : 



Si0 2 

 Ti0 2 



A1 2 



s 



Fe 2 8 



FeO 



MnO 



CaO 

 MgO 

 K 2 

 Na 2 



PA 



I 



4073 

 0-71 



20 62 

 552 

 513 



• • • • 



12-50 



8-75 

 090 

 303 

 1-41 



II 



4070 

 1-55 



14-89 

 7-05 

 6-81 



III 



39-32 



17-53 

 307 

 9 12 



• • 



* * 



12-21 

 9-92 

 117 

 2-78 

 1-39 

 0-76 



10-38 

 8-00 

 204 

 2-44 

 730 



* • 



IV 



38-62 



1-86 



1390 



597 



8-65 



030 



1554 



11-21 



57 



2-01 



1-46 



060 



99-30 



99-23 



99-20 100-69 



I. Limburgite from Hamandun. Analyst P. C. Chatter- 



II. Limburgite from Nonnenwald b Lauban, Lausta. 



(Osann : Beitr. Zur chem. Petrographe. II, Teil 



III. Limbu'rgile from Bendigo (Victoria) (Proc. Roy. Soc., 



Victoria n.s. Voh XXIV, p. W j dg 



IV. Limburgite from ^/^V^fw 



abunnte Irom ltiibMi *«— > ~-i ~±h\ 



(Prof. pap. no. 14, U.S. Geol. Sun., p. 347). 



^jrroi. pap. nu. a-*j v*~" ~ 



It is a matter of regret that very little J-Wf^^Jg 

 regarding the systematic analysis of the Indwn 

 and thus with the exception of a fej cawi 

 Washington « Dr. Walker,* and the data "*^ ]g fl 1 ri le 

 Fernior* in course of a discussion of the position of h* Koau 



1 Min. u. Petr. Mittheil. , Bd. XVII, p. 534 (1898). 



* Min. u. Petr. Mittheil., Bd. XX, p. 304 (l«» l ). 355> 

 3 Prof, paper No. 14, U.S. Geol. Surv., pp. \f' f' 



* Rec. Geol. Surv. Ind., Vol. XXX VI , pp- * £~ - fa igneo us nature 

 . ' Rec. Geol. Surv. Ind., Vol XLII, PP- ^ pr b evond doubt as in a 



°* the Kodurite series of rocks is not, however oey ^ ^ , the 



fnore recent communication Dr. Ferroor e*P res f** f ^ dism on a large 

 kodurite series may perchance be an e . xam P' e o ° e magnitude has bodily 

 seal* ;- whic , ' * graniti- intrusive of some ma b 



in 



a granitic intrusive 



