ALUMINA. 



337 



^^' ^"^^ of the acute lateral edges, the prismatique of Haiiy (Fig. 306), but 



differing in the relative size of the planes. The singular twin crystal, 

 Fig. 309, has been found here by Dr. Horton. 



Crystals of feldspar and adularia, usually small, are found in other 

 parts of the island, both in the quartz which traverses the limestone, 

 and in the fissures of gneiss. Cleavable masses, often of considerable 

 size, and sometimes having a reddish colour, also occur in similar situa- 

 tions. 



Orange County. Common feldspar is of course very abundant in this county. Fine speci- 

 mens having the primary form, and often of a flesh-red colour, occur in the vicinity of West- 

 Point. A beautiful white and opalescent variety occurs at Bog-meadow pond, in the town of 

 Cornwall. 



At the Long, Roberts, Patterson, Stirling and Rich iron mines, massive feldspar is com- 

 mon ; at the two latter, it is red. 



In the town of Warwick, it is found at Rocky hill, of a white colour. At McGee's hill, it 

 is red. 



Fig. 311. 



Fig. 310. 



Of crystallized feldspar, Rocky hill in 

 the town of Warwick is one of the most 

 interesting localities. The colours are 

 white, yellowish and reddish white. It 

 is associated with tourmaline and zircon. 

 There have been found here, the pm- 

 matique of Haiiy (Fig. 306) ; also the 

 unitaire of Haiiy, Fig. 310; and the 

 sexdecimal oi Haiiy, Fig. 311. 



P on 07 128° 51'; ^ 



P on y 99° 29' ; 



Mono; 90°. 



Fig. 312. 



Near Amity, there is found crystallized feldspar, which is white 



and yellowish white. The prismatique of Haiiy is met with, and 



sometimes twin crystals occur of the form represented in Fig. 312. 



There is also a locality of this variety about a mile northwest of 



Edenville, where it is associated with green tourmaline. 



Putnam County. On Hustis' farm, in the town of Phillipstown, 

 feldspar is found in laminae of considerable size, associated with 

 pyroxene, etc. It is of a reddish colour. 

 Richmond County. Feldspar, in thin plates, and in minute crystals having the primary 

 form, occurs in the fissure of greenstone near Port Richmond, formerly Merserole's ferry. 

 This locality is the so called Granite quarry. 

 MiN. — Part II. 43 



