CONTENTS. Vii 



Page. 

 Chapter VI. — Lower Silurian sericite-8<hiKt8 anil amphibolites on the west side of the valley — 



Continued. 



The Chester amphibolite and serpentines — Continued. 



Petrographical description — Continued. 



The serpentines and associated luagnesiau rocks — Continued. 



Olivine- and enstatite-serpentine 101 



E^sumiS 114 



Table of analyses of serpentines 116 



The Chester emery bed 117 



History of di.^^cnvery and working of the bed 117 



A description of the emery mine of Chester, Hampden County, Massachusetts, by 



Charles Upbam Shepard 122 



General description 135 



Association and paragenesis of the minerals of the emery vein 143 



Resume of paragenesis 147 



General explanation and correhition of the Chester amphibolite series 147 



Original condition of the enstatite-serpentine and limestone complex 147 



The Savoy schist = the upper serioite-schist 156 



Distribution 158 



Boundary upon the rocks below 156 



General description of rocks 157 



Comparison with the Rowe schist below 158 



Detailed description and sections 158 



The Shelburne anticline 162 



Petrographical description 162 



Intrusive rocks 163 



The Hawley schist 163 



Distribution 164 



Detailed description 164 



Petrographical description 166 



The possible igneous origin of the Hawley schist 169 



Mineral deposits 170 



The pyrite beds 170 



Copper (ires 171 



The great Hawley fault and the magnetite and hematite deposits, the rhodonite and rho- 



dochrosite beds, and the garnet-schist or coticule 171 



The Goshen anticline 175 



Chapter VII.— The graphitic mica-scMst series on the west side of the valley 177 



The Goshen schists or flags 177 



General description 177 



Unconformable contact on the rocks below ; outliers in the Hawley schist 179 



Petrographical description 181 



The Conway schists, or the corrugated mica-schists 183 



General description 183 



Subordinate beds in the Conway schist 185 



The gneiss beds 185 



The whetstone-schist 186 



Petrographical description 187 



