STRONTIA. 



211 



Jefferson County. At Brownville, rclcstine is said to have been found in slender crys- 

 tals ; and at Chaumont bay, in masses of a snow-white colour, made up of long and slender 

 prisms or needles, arranged in a radiated or stellated manner. Some of the specimens from 

 this locality arc nearly or quite pure. According to Dr. Emmons, this mineral occurs in the 

 water limestone found near Dcpcauvillc. 



Monroe County. Cclcstinc has been credited to the vicinity of Roclicstcr, where it has 

 been said to occur in nodules in the limestone. Most of the specimens which I have examined 

 are undoubtedly heavy spar, although it is quite probable that celestine may occur, as it is 

 very abundant in some of the limestones farther west. 



Niagara County. In the vicinity of Lockport, this mineral was first found in making ex- 

 cavations for the Eric canal. It has since been obtained in abundance in geodcs of various 

 sizes, often very large, associated with calcareous and pearl spar, selcnite, anhydrite, etc. 

 Two varieties occur, viz. the lamellar, and the coarsely fibrous. The lamellar variety is white 

 and bluish white, varying from opaque to semi-transparent. It is often made up of long and 

 slender crystals, which have the outline of the primary, or have the acute lateral edges replaced 

 by planes which are greatly extended, forming a long six-sided prism. The specific gravity 

 of the purest specimens varies from 3.80 to 3.95. It usually effervesces slightly in acids, 

 from the admixture of carbonate of lime. The fibrous variety is snow-white, and almost 

 friable. The fibres are straight, divergent or bent in various forms. It closely resembles the 

 Baryto-sulphate. of Strontian of Dr. Thomson, from Kingston, Upper Canada. 



Schoharie County. The fibrous variety is found in thin veins, in the vicinity of the 

 court-house. It is of a bluish colour, but is usually mixed with carbonate of lime. The 

 lamellar variety is also said to occur at the same locality. 



St. Lawrence County. Crystals of a deli- 



Fig. 48. 



Fig. 40. 



cate blue colour have been found in the Rossie 

 lead mine, associated with the bcautilul calca- 

 reous spar for which that locality is so justly 

 celebrated. They usually have the form of low 

 si.x-sided tables, resembling the hisunitaire of 

 Hauy. Fig. 48. P on s 90° 0'; P on o 128° 

 31'; n on o 102° 58'. These cry.stals are 

 somewhat convex on their broad surfaces, and 

 arc often deeply striated. Small four-sided 

 tables. Fig. 49, arc also found at this locality. 

 I add, on the authority of Dana, the figure (50) of a 

 crystal from Moss, or as it is now called, Strontian island, 

 situated at the southwestern extremity of Lake Erie, wiierc 

 this mineral is found in great abundance in the hmestonc. 

 In colour and other characters, it closely resembles one 

 of the varieties found at Lockport. P on I 157^ 47'; </on d 78° 28'; d on I 102° C9' 

 (Hauy). 



