58 Geology and Mineralogy of a part of Massachusetts, &c. 
11. SULPHURET OF MOLYBDENA. 
In beautiful plates or lamina—more brilliant lead colour, 
and less dark than foliated plumbago. I have some regu- 
lar hexaedral plates, which were closely united, fomaing a 
s1X sided prism, in quartz. Chesterfield. 
12, RED OXIDE OF TITANIUM. 
In small prisms in quartz associated with Dolomite in 
Pittsfield—rare. Also in flat plates in quartz in Middlefield ; 
Bymone. 
| 13. FERRUGINOUS OXIDE OF TITANIUM. 
It has some resemblance to schorl; but is infusible——oc- 
curs in smallish long imperfect nearly black prisms in gran- 
ite—-rare. Chester; Emmons. 
14. sILICO-CALCAREOUS OXIDE OF TITANIUM. 
In Middlefield in imperfect prisms, rather lighter colored, 
but much resembling that of Brattleborough, Vt. 
MINERALS OMITTED. 
Anthracite. 
This mineral is found in small quantity in gray wacke 
slate, especially at Schuyler’s quarry, Troy; Eaton. 
Vert Antique # 
This is a magnesian mineral found in a bed in gneiss on 
the river in Becket, and colored greenish by serpentine. 
It may, as Dr. Emmons supposes, be a serpentine marble. 
It is a tough mineral, and takes a fine polish. In some 
