172 GEOLOGY OF OLD HAMPSHIRE COUNTY, MASS. 



rhodonite. ^Mueh mining was done here in 1848, but it was abandoned 

 because of the Cahfornia gohl excitement. By following the road north a 

 mile and a half to a jioint where it turns sharp east, measm'ing 60 rods south 

 fi'om this bend, and going 10 rods east into the open field, one comes to 

 another opening on a vein or group of veins 10 feet wide, mostly quartz- 

 rhodonite veins, the unaltered rock faintly pink and the whole greatly 

 blackened by oxidation. These two openings are called, locally, the man- 

 ganese mines. They mark the line of a great fault, which runs south 

 through the area of iron-manganese in Hawley. An inspection of the map 

 will show that the amphibolite bands coming south are cut off with an acute 

 angle against this fault, and the contrast of the highly ferruginous ankerite- 

 chlorite-schists (Hawley schist) on the east and the barren quartzose 

 sericite-schists (Savoy schist) is everywhere very striking. 



Across Forge Hill, in West Hawley, this contact line bends consider- 

 ably to the east, but the crushed band, largely filled with quartz veins, more 

 or less ferruginous, is so wide here that I have represented the state of 

 things by doubling the fault line across this area. I was guided the whole 

 length of the iron deposits on Forge Hill, south of the old Hawley mine, 

 by Mr. M. V. Cress}^, who owns most of the land and has examined the 

 country for iron more carefully than anyone else. At the most southern 

 opening marked on the map, and the one where the dipping needle was most 

 affected, the schist was impregnated with magnetite for a thickness of 12 

 feet in the digging, and about 2 feet of this would pass as a lean ore. From 

 this point tlie vein or veins can be followed north for a long distance, and 

 opposite the south end of the amphibolite band and in the line of the 

 straight fault marked on the map considerable digging has been done and 

 the magnetite, here exceptionally abundant, is accompanied by much flesh- 

 colored quartzite, apparently colored by rhodonite and rhodochrosite. The 

 schist is full of magnetite for many rods to the east, and a well-marked 

 hematite vein occurs here, with the quartz-rhodonite mixture accom})anying 

 it. About 10 rods south of this the epidotic amphibolite comes to an 

 end and the ankerite-chlorite-schist abuts against the quartz-sericite-schist. 

 The vein can be followed north by disseminated ore to the Cressy "second 

 pasture," a mile south of the old mine. Here a deep shaft has been sunk 

 on the vein at the junction of the two rocks and masses of pure magnetite 

 were lying at its mouth, and the accompanying vein quartz here and along 



