THE MINING AND QUARRY INDUSTRY I914 '79 



west at angles of from 30 to 6o°, so that they are all worked by 

 underground methods. The wall rocks are limestone and schist 

 cf Precambric age, a part of the Adirondack crystalline formations. 

 The fibrous talc is an alteration product of tremolite which it re- 

 sembles in physical development, but the scaly talc apparently is 

 the result of deposition by underground waters. Altogether there 

 are fully fifteen or twenty different deposits, some of which, 

 however, are not profitable under present conditions, and others are 

 being held in reserve. The number of operative mines in recent 

 years has ranged from five to eight or nine. The mines are opened 

 by inclined shafts sunk on the footwall with levels driven from 

 either side at intervals of 100 feet or less. The mining is simple 

 and inexpensive, the main cost of the prepared talc being incidental 

 to the mill treatment which involves reduction by several stages 

 the final grinding being done in ball and tube mills. The final 

 grinding requires from two to five hours. 



The producers of talc in this district include the Ontario Talc 

 Co. with a mine and mill near Fullerville, the Uniform Fibrous 

 Talc Co. at Talcville, and the International Pulp Co. with mines 

 near Talcville and Sylvia lake and mills at Hailesboro near Gouver- 

 neur. The Standard Talc Co. has a mine near Talcville, which was 

 once worked by the United States Talc Co., but the company made 

 no output last year. The North Country Corporation has been 

 engaged lately in the development of a new deposit near Sylvia 

 lake, town of Fowler. 



The Gouverneur district first became an important shipper of 

 ground talc about 1880, when the output amounted to 4000 tons, 

 but it was developed a few years before that date. The production 

 since has been continuous and in the last 20 years has averaged 

 about 60,000 tons. The total product since the beginning has 

 amounted to over 1,600,000 tons, worth about $14,000,000 at the 

 average prices received at Gouverneur. 



A deposit of talc neap Natural Bridge has been worked for the 

 last four years, and has supplied a considerable quantity of material 

 which is sold in ground form. This deposit occurs in limestones, 

 but in a separate area from the Gouverneur belt and has a quite 

 different character. The talc lacks any definite structure, except 

 that it shows a granular appearance in places, and is associated with 

 other hydrated silicates of the serpentine and chlorite groups. It 

 appears to be a contact deposit, lying near an intrusion of granite. 

 An analysis of the material was given in the last previous issue 

 of this report. The mine is operated by the St Lawrence Talc Co., 



