106 
MINERAL PRODUCTS 
§ 1. Brown hematite, and oxide of manganese. 
The brown hematite and oxide of manganese are associated in the same beds, and are 
derived from sources originally the same. I have already stated that the Stockbridge lime¬ 
stone often passes into thin talcose strata, in which a peculiar ferruginous looking sub¬ 
stance abounds. These layers, by exposure to the atmosphere, become yellow from the 
presence of ochre which appears diffused through them. But they always disintegrate 
rapidly, and form deep yellow clays, which, on being penetrated, furnish nodules of oxide 
of iron ; or, in places where there is a great accumulation, beds of the ore are found lying 
wholly disconnected with the rock in the common acceptation of the word. In some in¬ 
stances the ore is collected in beds in a line drift, or soft material containing round pebbles, 
frequently granular quartz, and occasionally stockbridge limestone. It is difficult to de¬ 
termine whether the materials forming these beds have been transported or not. They 
appear to have been carried into depressions by the slow operation of common or ordinary 
causes, simultaneously with the disintegration and decomposition that detached and sepa¬ 
rated the particles from their common matrix. The beds thus formed may have been 
enveloped in drift, with the partial destruction of the accumulated materials. 
The hematite embraces the usual varieties of imitative forms, as botryoidal, mammillary, 
stalactitic, etc. Large globular hollow masses are often met with in the excavations, of 
sufficient capacity to hold a barrel of water, and sometimes water is found in them. The 
interior of these large globes is lined with a splendent coating of manganesian matter, 
spread over the vertical fibres which terminate inwards. The outside is always rough with 
projecting points of hardened ore. 
The manganese is usually collected in masses amidst the iron ore: it is in imperfectly 
compacted masses, or in that condition called wad. In other instances, it is in hard rough 
black masses, with a fine granular or earthy texture; and sometimes in fine needlefonn 
crystals of exceedingly high metallic lustre. 
A range of beds of hematite extends from Westchester county, through Salisbury, 
Amenia, Stockbridge, Richmond, Bennington, and onwards to the Canada line. All 
the independent ranges of the Taconic rocks furnish beds of hematite. 
Associated with the same beds is the gibbsite, an aluminous mineral occurring in the 
form of incrustations, and pendent among the masses of ore in stalactites or tuberous 
masses. Fine white clays also abound, which appear of the same composition as the 
gibbsite. White carbonate of iron is also quite common, usually in rounded or kidney- 
form masses. 
The different minerals enumerated above are derived from the magnesian slates and 
limestones, and not from the taconic slate. 
