Miscellaneous Notices of Mineral Localities, fyc. 225 



Canaan furnishes several other interesting minerals, which 

 have been noticed in the journals and mineralogical books. 

 In the limestone, a large part of which is dolomite, between 

 the mountain just described and the south meeting house, 

 occurs abundance of crystallized white augite. The lime- 

 stone is very liable to disintegration, and by a little search in 

 the white soil above the rock, the augite may be found in a 

 perfect state. Some of the crystals are six sided prisms, with 

 two lateral planes broader than the others. These are ter- 

 minated by four sided summits, whose faces correspond to 

 the nearest faces of the prism. Sometimes the terminal 

 edge of the summit is truncated. Sometimes in addition to 

 this truncation, one, two, three or four of the solid angles of 

 the summit are replaced by planes. This six sided prism is 

 often converted into an eight sided one, by a slight truncation 

 on its acute lateral edges. This truncation is sometimes so 

 deep that the crystal becomes a perfect four sided prism, 

 with slight truncations on all its angles. 



In the same limestone exists abundance of very beautiful 

 tremolite. If I mistake not, all the varieties of this mineral 

 exist here; viz. the common, in flattened prisms ; the fibrous, 

 exceedingly delicate, resembling white silk ; and the baika- 

 lite, in acicular radiating prisms. 



Quartz Rock. 



By consulting Professor Dewey's geological map of Berk- 

 shire county, we find that he has put down quartz rock in 

 several places, and in Canaan among the rest. I understand 

 him, however, in common with all American geologists, to 

 embrace in his description, only that variety of this rock, 

 which consists of granular and compact quartz alone. But 

 if I mistake not, several other varieties of the quartz rock of 

 Dr. Macculloch, occur in this country, and have been usually 

 confounded with mica slate. I reckon among these, the 

 high and precipitous mountain a few rods south east of the 

 south meeting house in Canaan. It is composed of quartz 

 and mica, the quartz predominating : and this is the charac- 

 ter by which Dr. Macculloch distinguishes this rock from 

 mica slate. It rarely has a schistose structure, but is rather 

 indistinctly stratified. The quartz being white, the rock 

 would easily be mistaken for granite, or gneiss : but I could 

 discover in it no feldspar. This same rock I have observed 

 in several other places, in connexion with the mica slate of 



Vol. XIV.— No. 2. 3 



