32 Mineralogy of New York. 



The number of species detected in the state is one hundred 

 and fifty. In the following remarks it will be most convenient 

 to follow the course of the work, and extract such facts under the 

 several species as may be new. 



One new species, proposed by Prof. Beck, we may first notice. 

 It is named Hudsonite. It belongs to the augite family, and as 

 Rammelsberg remarks of the closely allied mineral, Polylite, 

 (Handworterbuch, II, 69,) it is near the variety Hedenbergite. 

 In cleavage and angles it resembles a massive black augite. H.= 

 45 — 5. G.— 3-5. Lustre vitreous, resinous, opaque. Before the 

 blowpipe it fuses with effervescence to a black bead, attractable 

 by the magnet. Composition according to Prof. Beck, silica 

 3790, oxyd of iron 3680, alumina 12-70, lime 11-40, magnesia 

 1-92. Except in the absence of oxyd of manganese, it differs 

 but little from Polylite. It was found by Dr. Horton in a vein 

 of quartz in the town of Cornwall, Orange Co. The Polylite of 

 Thomson is stated to have come from Hoboken ; but Prof. Beck 

 remarks that this must be an error, as no bed of magnetic iron 

 ore, in which it was said to occur, is known to exist there. 



The Enpyrchroite of Prof. Emmons, is shown by Prof. Beck, 

 to be a mammillated phosphate of iron, and the Chiltonile of the 

 same author, to be Prehnite. The Rensselaerite is shown to be 

 a steatitic pyroxene, quite similar to the steatitic pyroxenes of 

 Sahla, analyzed by Rose. Its crystallizations, when distinct, 

 have the form and angles of pyroxene. On analysis, Prof. B. 

 found a specimen from Canton, St. Lawrence Co., to consist of 

 silica 5975, magnesia 32-90, lime 1-00, peroxyd of iron 3-40, 

 water 285. It fuses with difficulty before the blowpipe to a 

 white enamel. It occurs of white, gray and green colors, often 

 dark or even black. The light colored varieties are sometimes 

 translucent. H. =3 — 4. G. =2-874. It is easily worked in a 

 lathe, admits of a neat polish, and is wrought quite extensively 

 into inkstands, &c. 



We proceed with the species in the order of the work. 



Heavy Spar. — At Schoharie, heavy spar is mechanically mixed 

 with slrontianite and carbonate of lime. The calstronbaryte of 

 Prof. Shepard is one of these mechanical compounds, (p. 207.) 

 At Carlisle also a fibrous heavy spar contains largely of carbonate 

 of lime, and "in some places seems to pass into fibrous carbonate 

 of lime, by almost insensible gradations." The fibres are from a 



