328 University of California Publications in Geology [Vol. 10 



PAGE 



Minerals associated with the intrusives 349 



Feldspars 349 



Augite 349 



Hornblende and biotite 349 



Titanite _ _ 349 



Zircon 349 



Epidote 349 



Quartz '. 350 



Tourmaline 350 



Axinite 350 



Datolite 350 



Scapolite 350 



Apophyllite 350 



Okenite 351 



Prehnite 351 



Laumontite 352 



Opal 352 



Sulphide minerals 352 



Oxydation products 353 



Description op the Rocks 

 igneous inteusives and metamorpiiism 



At Crestmore, about eight miles westerly from Riverside, there is 

 an isolated mass of granodiorite with a capping of crystalline limestone 

 which is of exceptional interest because of the many minerals developed 

 in the limestone by contact and hydrothermal metamorphism. 



The Riverside Portland Cement Company's plant, situated at the 

 base of the hill, uses both rocks in the manufacture of cement. The 

 extensive quarrying is rapidly destroying the hills, and the different 

 minerals and associations almost daily brought to view are immediately 

 carted to the rock-crushers, so that a vast amount of material of 

 scientific value and many fine specimens are lost. 



The writer visited the quarries a few years ago and collected much 

 of the material described here, but no detailed study of the deposits 

 was made and no opportunity has presented itself for a second visit. 

 Specimens have been collected by others and sent to the University, 

 which have been of great help in making the list complete, and special 

 thanks are due Mr. L. J. Childs of Rialto. He has kept in touch with 

 the quarrying and collected minerals that otherwise would have been 

 lost, and these with notes of their occurrence have been given to the 

 writer. About fifty minerals are described in this paper, but these 

 represent only a portion of what probably could be found by daily 



