THE NONMETALLIC MINERALS. 309 



Norwich) [Specimen No. 62579, U.S.N. M.], and Sterling, MasHachusetts; atWindhani, 

 Maine, with garnet and stanrolite; at Peru witli beryl, triphylite, petalite; at Parin, 

 in Oxford County [Specimen No. 62578, U.S.N.M.]; at Winchester, New Hampshire; 

 at Brookfield, Connecticut, a few rods north of Tomlinson's tavern, in small grayish 

 or greenish white individuals looking like feldsi)ar; at Branchvillc, Ccmnecticut, in a 

 vein of pegmatite, with lithiophilite, uraninite, several manganesian phosphates, etc. ; 

 the crystals are often of immense size, embedded in quartz; near Stony Point, Alex- 

 andci- County, North Carolina, the variety hiddenite in cavities in a gneissoid rock 

 with beryl (emerald), monazite, rutile, allanite, quartz, mica, etc.; near Ballground, 

 Cherokee County, Georgia; in South Dakota at the Etta tin mine m Pennington 

 County, in immense crystals. [Specimen No. 73,642, U.S.N.M.]. At Huntington, 

 Massachusetts, it is associated with triphylite, mica, beryl, and albite; one crystal 

 from this locality was 16j inches long and 10 inches in girth. 



At the Etta tin mine, in the Black Hills of South Dakota, the mineral 

 occurs, according- to W. P. Blake, in sizes the mag-nitude of which 

 exceeds all records. Crystalline masses extend across the face of the 

 open cut from 2 to feet in length and from a few inches to 12 and 18 

 inches in diameter. Blocks too large to lift have been freely tumbled 

 over the dump with the waste of the feldspar, (juartz, and mica. The 

 gigantic crj^stals preserve the cleavage characteristics and show the 

 common prismatic planes. The color is lighter and is without the 

 delicate creamy pink hue of the specimens from Massachusetts. It is 

 very hard, compact, and tough, and is difficult to break across the 

 grain. Some of the fragments are translucent. 



The chief foreign localities of spodumene are Uto in Sodermanland, 

 Sweden, where it is associated with magnetic iron ore, tourmalines, 

 quartz, and feldspar; near Sterzing and Lisens, in Tyrol; embedded in 

 granite at Killiney Bay near Dublin, and at Peterhead, Scotland. 



l/f^es. — So far as the writer is aware, the mineral has as yet been put 

 to no economic use. There seems no reason for its not being utilized 

 as a source of lithia salts as well as amblygonite and lepidolite. 



Petalite, another lithium aluminum silicate containing 2.5 to 5 per 

 cent lithia occurs associated with lepidolite, tourmaline, and spodumene 

 in an iron mine at Uto, Sweden (Specimen No. (52582, U.S.N.M.), with 

 spodumene and albite at Peru, Maine, and with scapolite at Bolton, 

 Massachusetts. 



T. Lazurite; Lapis Lazuli; or Native Ultramarine. 



Composition essentially Na^ (NaSg.Al) Al2Si30i2,= silica, 31.7 per 

 cent; alumina, 26.9 per cent; soda, 27.3 per cent; sulphur, 16.9 per 

 cent; hardness, 5.5; specific gravity, 2.38 to 2.45. Color, rich azure- 

 violet or greenish blue, translucent to opaque. The ordinary lapis 

 lazuli is not a simple mineral as given above, but a mixture of lazurite, 

 hauynite, and various other minerals. 



