SILK \TI.>. TITANATI'.S, I.T< 



427 



Keen uncovered ; the mineral is mined there for the manufacture of 

 lithium compounds. Then' is a lamellar structure very often 

 developed parallel to the ort hopinacoid and when prominent yields 

 a parting. 



Spodnnieiie occurs in the pegmatites of New England, as at 

 Mount Mica and Windham, Maine ; at Goshen, Massachusetts, and 

 Branchville, Connecticut. In these pegmatites it is associated with 



Fio. 474. Spodumene. Goshen, Massachusetts. 



tourmaline, amblygonite, lepidolite, and beryl. The green variety, 

 hiddenite, is found in cavities in a gneiss-like rock at Stony Point, 

 Alexander County, North Carolina, , where it is associated with a 

 clear green beryl. 



Kunzite, a lilac-colored variety, is mined at Pala, San Diego 

 County, California. Both of these clear colored varieties are used 

 as gems ; beautiful specimens have lately been discovered in a coarse 

 pegmatite in the island of Madagascar, where they are asso- 

 ciated with magnificent tourmalines, lepidolite, and the pink beryl 

 (morganite). 



By an interchange of alkali, spodumene alters to albite, micro- 

 line, or muscovite. 



PECTOLITE 



Pectolite. An acid sodium calcium metasilicate, HNaCaa,- 

 (SiO 3 ) 3 ; NasO = 9.3, CaO = 33.8, SiO 2 = 54.2, H 2 O = 2.7 ; Mono- 



