50 Geology of Massachusetts. 
as at Chelmsford, Chesterfield, Chester, Williamsburgh and Blan- 
ford; and sometimes, I am inclined to believe, of a good quality to 
be wrought into ornamental articles; particularly, at one or two lo- 
calities recently discovered. The amethyst, which occurs in green- 
stone, along Connecticut river, is of a delicate color, and, if it can 
be obtained in sufficient quantity, may be employed in the ornamen- 
tal arts. 
Some of the adularia that is common in the gneiss of Brimfield, 
Southbridge, &c. I presume, would answer well for watch seals, 
rings and trinkets; particularly, a greenish variety, occurring near 
the center of the latter place. Ihave seen an elegant watch seal, 
cut from the adularia of this locality. * — 
Tt ought not to be forgotten, that amber has been found in Martha’s 
Vineyard, at Gay Head, and on Nantucket. At the latter place, one 
or two masses were found, weighing a pound or more. ‘The tertiary 
“formation of these islands is precisely the place where we might ex- 
pect to find this mineral, especially in connexion with the lignite. 
METALS AND THEIR ORES. 
It remains only, in giving the economical geology of Massachusetts, 
to describe the metals and metallic ores which have been found in 
the state, and are applicable to useful purposes. I shall begin with 
the metal most abundant and most useful: viz. : 
Tron. 
The bog iron ore is most common, but I shall give an account of 
the different species in regular order j 
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. 
