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General View of the County

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We observe, that at a meeting of the geologists and naturalists of the Union, held in the city of New York, in September, 1846, Mr. Alger made the following observations, which support the remarks of Dr. Fowler, and bring to light new and Interesting facts connected with the mineral wealth of the County:

“The zinc mines are situated in the Walkill Valley of New Jersey, which extends nearly in a north and south direction through Sussex Co.— Towards the south limits of this valley, near Sparta, there commences a long range of hills, which extend through Sterling to Franklin. These hills consist principally of granular limestone, (the altered blue limestone of Prof. Rogers,) and it is in these formations that the zinc deposites occur. The bed visibly exposed at Sterling is about 600 feet. Assuming its present average width at four feet, and its depth at 100 feet, we have 240,000 cubic feet of ore. Each foot of this contains 170 lbs. of red oxide, and as the oxide of zinc contains 81 per cent, of pure metal, the whole amount at this single locality is 33,048,000. At five cents per lb., the average price, this one deposite would be worth nearly two millions of dollars.

“Mr. Alger stated that in Edenville, N. Y., he had met with a curious substance, the nature of which he had no means of determining at the time. It came from the village of Amity, Orange County, in this State—has no crystalline structure, but appeals in thin layers or seams, of a peach blossom or purple color, penetrating limestone. He soon discovered it to be Yttrocerite, both by an examination of its pyrognostic character and a careful comparison of its physical character with the mineral from Finbo in Sweden. On being placed in a crucible, and on the application of heat, hydrofluoric acid was obtained, producing the usual reaction on a plate of glass. Mr. A. thought this must be considered as the first well authenticated instance of the occurrence of this exceedingly rare mineral at in the United States, or at least the first undoubted locality. He was aware that President Hitchcock had found a specimen which he had supposed to be Yttro-cerite, which was analyzed by Dr. Jackson and proved to have been that mineral. Prof. Hitchcock supposed he had taken that specimen from some part of Worcester Co., Mass.”

The clay beds of the tertiary deposites are extensive in the County, out of which a coarse pottery is made; but their principal economical use is in the manufacture of brick, of which there are about 10,000,000 annually made. These deposites extend along the values of streams, and are found 500 feet above the Hudson. Those on the Hudson are from 150 to 200 above tide water.