LIME. 



219 



passes into the white, opaque or transparent ones. The exterior of these crystals is always 

 more or less rough, but they are often translucent throughout, in which case the peculiar 



tint can be distinctly seen. They are some- 



Fig. 66. 



Fig. 67. 



times a foot or more in length, and some have 

 been found weighing nearly one hundred 

 pounds. A striking peculiarity of many of 

 the crystals is, that three sides of the rhom- 

 bohedron are perfect, while the others are 

 drawn out into the form of the hog-tooth spar, 

 the summit having a kind of cap of a different 

 colour from the body of the crystal, and 

 having the appearance of a subsequent de- 

 posit. They are indeed sections of dodeca- 

 hedrons built upon the primitive rhombohe- 

 dron, but which either the position of the 

 crystal, or some other cause, has prevented the completion of, on the opposite side. I have 

 endeavored to represent them in Figures 66 and 67. P on r 151° 3'. 



Four miles south of Oxbow, in the town of Antwerp, and on the road to that village, an 

 excavation for lead ore as usual opened a fine vein of calcareous spar. Large masses and 

 imperfect crystals were found, from which beautiful cleavage crystals have been obtained. 

 They are white, purple and brownish, as at the preceding locality. They usually have a 

 lustre which is more highly vitreous than it is in any specimens of this kind which I have 

 seen. 



At this locality, there have also been found crys- 

 tals in the form of six-sided prisms, prismatique of 

 Haiiy (Fig. 68) ; and in that of the scalene dodeca- 

 hedron terminated by three rhomboidal faces, binaire 

 of Haiiy (Fig. 69). c on o 90° 0' ; c on c 120° (V. 

 P on r 151° 3' ; r on r 144° 20' 26" ; r on r' 104° 

 28' 40"; r onr" 133° 26'. 



On the east bank of Vrooman lake, a mile north- 

 west of the village of Oxbow, calcareous spar is 

 found in abundance in veins in the primary rock, 

 associated with crystallized (Quartz. The forms are 

 the binaire of Haiiy (Fig. 69), and the rhombohe- 

 dron with two or more of the edges replaced by new 

 planes. Numerous crystals are usually grouped together, in such a manner as to exhibit a 

 very complicated arrangement. This is a locality well worthy the notice of the mineralogist. 



Fig. 68. 



Fig. 69. 



