108 JOUENAL OF THE MiTCHELL SoCIETY \_AugUSt 



conia, a station on the Southern Eailroad, was largely due to 

 the efforts of Mr. W. E. Hidden. Zircon was first discovered 

 here in 1869 but no special importance was attached to it; and 

 the first shipment was in 1888. Although the shipments of 

 the zircon from this locality were never very largie, yet they sup- 

 plied the necessary material for use in the manufacture of the 

 mantles for incandescent lights. Experiments regarding the 

 most suitable material for the manufacture of these mantles 

 were continued in the laboratories of the different companies, 

 and in a few years it was discovered that thoria made a better 

 mantle than zirconia, and therefore the dem'and for zircon be- 

 gan to decrease, until finally its production entirely ceased. 



A new use, however, 'arose for zirconia — to t>e used in the 

 manufacture of the glower of the N^^ernst electric lamp, and in 

 1902, mining for zircon on a small scale was again commenced 

 at the Jones mine and has continued to the present time. In 

 1911 the Freeman mine, adjoining the Jones mine, also became 

 a producer. 



Associated with the zircon in these mines is auerlite ^, 

 a mineral that contains approximately 70 per cent, of thorium 

 oxide. It has been considered a hydrous silico-phosphate of 

 thorium. 



A special search will be made for auerlite while mining 

 for zircon, and several kilograms have already been obtained. 



ISTear jS^ew Sterling, Iredell County, a great many brownish, 

 pyramiidal crystals of zircon have been found in the soil, some 

 of which were 1 to 3 inches in diameter. One crystal weighed 

 about 6 ounces. The exact occurrence of these crystals has not 

 as yet been definitely determined, but thus far there has been 

 observed no indication of a commercial quantity. 



There are small quantities of zircon found in all the mona- 

 zite sands, which could probably be saved as a by-product. 

 These crystals are very minute, and are transparent. 



Gadolinite ^^ : — There is also used in the manufacture of 

 the glower for the ISTernst lamp, yttria, which is found in some 



»Am. Jour. Sci., Ill, vol. XXXVI, 1888, p. 46. 



lou. S. Geol. Survey, Mineral Resources, pt. II, 1911, p. 1195... 



