ALUMINA. 331 



Fig. 282, the dioctaedre of Haiiy, in which the replacing tangent planes are broader ; 

 Fig. 283, in which two of the replacing planes are much larger than the other two, giving 

 the crystal a flattened form ; 

 Fig. 284, in which the edge between I and I is replaced by the plane t ; 

 Fig. 285, in which the edge between M and I is replaced by the plane z ; 



Fig. 282. 



Fig. 283. 



Fig. 284. 



Fig. 285. 



M 



V^ 



1 M 



M 



M 



M 



Also Figs. 286, 287, and a modification of the triplante of Haiiy, Fig. 288. 



M onZ 112° 30' 



Fig. 280. 



Fig. 288. 



M 



M 



M 



M 



M 



M 



M on s 135° OCK 

 M on t 113° 34' 

 Mono; 153° 26' 

 Mon^; 140° 11' 

 I on / 136° 22' 

 I on s 122° 10' 

 I on t 158° 11' 

 1 on z 151° 38' 

 s on a; 161° 34' 

 z onz 150° 18' {Haity). 

 Orange County. There are several localities of scapolite in this county. Near West- 

 Point, it is in large, white and compact masses, associated with pyroxene. At Fall hill in the 

 town of Monroe, there is a very compact variety of a white and bluish white colour, and 

 having a flat conchoidal fracture. It is associated with the beautiful lamellar pyroxene, here- 

 tofore noticed. 



At Two-ponds in the same town, there is a remarkable locality of crystallized scapolite. 

 The crystals are white and reddish white, opaque, and sometimes rough. They are often 

 very large, and grouped. One of them is nearly ten inches in length, and five inches in 

 diameter. It is associated with pyroxene, sphene and zircon. 



The same variety is also found at Greenwood furnace ; while that which has been called 

 Meionite, but which is seldom transparent, occurs in the form of minute crystals or grains in 

 Umestone at the Two ponds, the Forest of Dean and elsewhere. It is often associated with 

 red calcareous spar. 



