) 



Mineratogkal Journey. ■ 127 



I 



an abundance of Garnets scarcely larger llian those above described, 

 and like them remarkable on acconnt of their uniformity in shape; 

 which, in the present case, is that of the elongated dodecahedron. 

 Their gangue is a. mica-slate rock, consisting, almost entirely, of a 



with 



Wh 



it is traversed by large seams of quartz, a delicate blue Cyanite Is 

 sometimes observed, as also crystals of Rutile. 



5. Staurotide of Mink Pond. 



In the town of LandafF, about eight miles beyond Bath, on ilie 

 road to Franconia, we visited a deposit of Staurotide, the most re- 

 markable in the United States, if we consider the size and perfection 

 of the crystals, their abundance, and the readiness with which they 

 are capable of being disengaged from their gangue. It was first 

 made known to us by Gen. Field of New Fane, by whom, if I mis- 

 take not, it was discovered. It occurs directly opposite Mink Pond, 

 by the side of which the public road passes. Leaving this road, a 

 few rods east of a small dwelling house, and ascending a moderate 



rise of ground, we passed over enormous tables and uptom masses 

 of gneiss, completely covered with, and penetrated by, the crystals 

 of Staurotide. The gneiss is composed of quartz and feldspar, in 

 fine grains, imperfectly separated into layers by minute scales of 

 black mica J its texture is rendered very weak, in consequence of an 

 incipient disintegration and the abundance of the imbedded mineral. 



The crystals which vary in dimensions from one half of an inch, to 

 two inches in length, are of a reddish brown color and translucent on rhe 

 edges. They occur, for the most part, singly, and In tlie form of die 

 primary crystal of llie species, a right rhombic prism, Avith the exception 

 of the very slight truncation ofits acute lateral edges. More rarely, crys- 

 tals are observed having tliese narrow secondary faces enlarged until 

 they nearly equal in width the adjacent primary planes, thus forming 

 the equilateral six sided prism ; (perihejcacdre, H.) The compound 

 forms are still less common ; though the two usual kinds (geminee 

 rectangulaire and geminee obliqnangJe, H.) are occasionally met 

 with, the composition being formed of Individuals of the same shape 

 with those first described. Crystals of dodecahedral Garnet fre- 

 quently penetrate tlie Staurotides ; but without any observable uni- 

 formity in the position of the axes of the penetrating crj'stals, like 

 what, under similar circumstances, is seen to obtain between the 

 Staurotide and Cyanite of St. Gothard. 



