254 PHYSIOGRAPHY. 



Heavy Spar Hedyphane. 



as in foliated masses, associated with crystallized Quartz, Green Mala- 

 chite and Vitreous Copper, all of which minerals are imbedded in sand- 

 stone. An extremely delicate, fibrous, nearly compact variety, is found 

 in great abundance, at Pillar Point, Jefferson co. near Sacket's Harbor, 

 (N.Y.) where it forms large veins. Its colors are reddish-brown, and 

 yellowish and greyish white. At the Perkiomen lead-mine in Pennsyl- 

 vania, are found the foliated, the compact and the earthy varieties. Hea- 

 vy Spar is extremely abundant in the Missouri lead-mines, and through- 

 out the southern and western States generally. It occurs at Schoharie, 

 (N. Y.) associated with Strontianite in the water-limerock. 



5. Little use has heretofore been made of Heavy Spar. Pure white 

 varieties are used as a white paint, either alone, or mixed with white 

 lead. The fibrous variety of various colors, from Pillar Point, (N.Y.) 

 has been sawn into moderately sized slabs, and polished ; many of which 

 present a very handsome appearance. 



HEDENBERGITE. (See Pyroxene.) 

 HEDYPHANE. He dy phanous Le ad-Bary te. 



Massive : composition granular and impalpable. Frac- 

 ture small and imperfectly conchoidal ; occasionally exhib- 

 iting little fissures. 



Lustre adamantine to resinous. Color, greyish white. 

 Translucent. 



Hardness =4-5 . . . 5-0. (Scale of BREITHAUPT.) Sp. 

 gr. =5-461 . . . 5-498. 



1. Before the blow-pipe, it melts into a white frit, but less easily than 

 the Mimetene. The lead is not reduced, even in the strongest heat of 

 the reduction flame ; nor does the resulting mass assume a polyhedral 

 figure. The arsenical odor is rarely perceptible. 



2. Analysis.' 



Oxide of lead .... 53-00 



Muriatic acid . 2.00 



Lime .... 14-00 



Arsenic acid .... 22-80 



Phosphoric acid . . . . ' 8-20 



