52 



Economical Geology. 



Mine of Arsenical Iron and Carbonate of Iron, in Worcester. 



In the town of Worcester, in mica slate, is a bed of these ores, 

 which was explored to some depth, a number of years ago, in search 

 of the precious metals. A little galena or lead ore is found also, in 

 the same mine. As the excavations are now nearly filled up, it is 

 impossible to judge of the extent of this bed. 



Arsenical iron is seldom explored for the purpose of getting malle- 

 able iron from it ; although it is sometimes employed for the arsenic 

 it contains, and for the preparation of sulphuret of arsenic. The 

 carbonate of iron is an excellent ore ; and has received the name of 

 steel ore, because it may be readily converted into steel. 



Mine of Carbonate of Iron and Zinc, in Sterling. 



This is a bed, in mica slate, just like that at Worcester ; and was 

 extensively explored forty or fifty years ago, for the same purpose 

 which led to the opening of that bed, viz. the discovery of gold and 

 silver. The carbonate is the most abundant ore, and lies scattered 

 about the excavation, in considerable quantities ; although the sulphu- 

 ret is common, which is sometimes arsenical. A reddish, foilated sul- 

 phuret of Zinc also occurs here, in considerable quantity, and some 

 sulphuret of lead. Whether this mine will be found worth exploring, 

 it is difficult, in its present state, to determine. If it afford the car- 

 bonate of iron in large quantities, it will certainly repay the effort. It 

 lies about a mile and a half south east of the center of the town. 



Chr ornate of Iron. 



It ought to be recollected, that a small rounded mass of this ore, 

 so valuable in the preparation of the paint called chrome yellow, was 

 found, a few years since, in Cummin gton, by Dr. Porter. 



Postscript. While the second edition of this Report was passing 

 through the press, I have discovered the chromate of Iron in serpen- 

 tine in Blandford. The serpentine itself has been brought to light 

 since the printing of the first edition, and occurs in the northwest part 

 of this town. The chromate is disseminated through the serpentine 

 and exists in it also in considerable masses, or in veins. I picked up 

 specimens of from four to five pounds weight ; but made no explora- 

 tion to ascertain the quantity in the rock. The mineralogical char- 

 acter of this mineral will be reserved for the third part of the report. 

 It is hoped that this notice will call the attention of practical men to 

 this locality. 



