THE 
AMERICAN GEOLOGIST. 
Vol. XXXIII. JUNE, 1904. No. 6. 
ON THE LAMPROPHYRES AND ASSOCIATED IG- 
NEOUS ROCKS OF THE ROSSLAND MINING 
DISTRICT, BRITISH COLUMBIA.* 
By William Burton Bakber, Alameda, Cal. 
PLATES XXIII-XXVIII. 
CONTENTS. 
Introduction. 
Lamprophyres 336 
Kersantyte 336 
Augite Camptonyte 338 
Transitional Rocks ^.^9 
Camptonyte _ 3.^9 
Minette 34.0 
Vogesyte 3+1 
Granular Rocks. 
Monzony te 342 
Basic Monzonyte 34.3 
Syenyte-Monzonyte 34.3 
Syenyte Dike 3+4. 
Syenyte Porphyry 34.4. 
Hornblende Dloryte 34.5 
Dioryte Porphyry 345 
Summary and Conclusion. 
Introducton. 
The entire area of the Rossland Mining District is made up 
almost entirely of eruptive rocks. The main body of this erup- 
tive is dioryte. Little or no sedimentary deposits are found in 
the district, t 
The great mass of dioryte was strained from north to south, 
opening up a nearly vertical and often parallel system of fis- 
sures. These fissures have a general easterly and westerly 
•The writer Is Indebted to Dr. J. P. Smith of Stanford University for 
assistance and advice. 
tThe notes on the general geology of this district are taken from the 
testimony of Mr. Clarence King In the law suit of the Iron Mask Gold Min- 
ing Company vs. Center Star Mining and Smelting Company before the Su- 
preme Court of British Columbia. April. 1899. pp. 6-10. 
