ELIZABETHTOWN AND PORT HENRY QUADRANGLES l6l 



of silicates in the Grenville limestone quarries and occasionally 

 yields platy crystals suggestive of its characteristic forms but too 

 rounded for sharp determination. 



Quartz. The large mines have yielded a few good quartz crys- 

 tals of the smoky variety. The pegmatites have corroded and 

 rounded dihexahedrons. The most interesting occurrence is, how- 

 ever, the rose quartz which is obtained in pits just west of the 

 road from Port Henry to Cheever and about a mile and a half 

 from the former. The color is very beautiful and the amount 

 quite unusual. It forms veins in the Grenville series. 



Rutile appears in the bunches of silicates in the quarries of 

 Grenville limestone, in somewhat scarce striated prisms and in 

 irregular fragments. 



Scapolite, see under Wernerite. 



Serpentine appears in masses often of very attractive dark 

 green color in the ophicalcite exposures. An analysis is given 

 above under pyroxene. 



Siderite appears in small cross veinlets in the Ivliller pit. It 

 forms a crust under calcite. 



Titanite appears both in the hornblendic masses in the Barton 

 Hill ores and in the bunches of silicates in the Grenville limestone 

 quarries, especially the one just north of Port Henry. On Barton 

 hill they are of large size and beauty reaching 2 inches across. 

 The faces are the usual combination of a steep pyramid and the 

 prism. 



Wernerite has been yielded by the upper pits on Barton hill, in 

 very excellent square prisms capped by the low pyramid. 



Fig. 3 5 Zirc^n crystal from Fig. 36 Zircon crystal from 



Mire "21" Barton fiill mines 



Wollastonite occasionally appears in the Grenville limestones 

 riorth of Elizabethtown. Its best locality is, however, in the 

 Ausable quadrangle next north. 



