COMPOUNDS OF BARIUM AND STRONTIUM. 991 
with soda in the reducing flame on coal, and then placed 
on a silver coin and moistened, it produces a black stain, 
due to sulphur. 
eBarite is often present in mineral veins as the ganeue of 
the ore. In this way it occurs at Cheshire, Conn.; Hat- 
field, Mass.; Rossie and Hammond, New York; Perkio- 
men, Pennsylvania, and the lead mines of the Mississippi 
Valley. Scoharie, and Pillar Point near Sackett’s Harbor, 
are other localities; also near Fredericksburg and elsewhere, 
Virginia; Nova Scotia, ete. The variety from Pillar Point 
receives a fine polish and looks like marble, the colors being 
in bands or clouds. 
Heavy spar is ground up and used to adulterate white 
lead. When white lead is mixed in equal parts with it, 
it is sometimes called Venice white, and another quality 
with twice its weight of barite is called Hamburg white, 
and another, one-third white lead, is called Dutch white. 
When the material is very white, a proportion of it gives 
greater opacity to the color, and protects the lead from 
being speedily blackened by sulphurous vapors; and these 
mixtures are therefore prererred for certain kinds of painting, 
Drcelite is a barium-calcium sulphate, 
Witherite.—Barium Carbonate. 
Trimetric. JA f=118° 30’. »Cleavage imperfect. Also 
in globular or botryoidal forms: often massive, and either 
fibrous or granular. The mas- 
sive varieties have usually a yellow- 
ish or grayish-white color, with a 
lustre a little resinous, and are 
translucent. The crystals are often 
white and nearly transparent. H. 
=3-4. G.=4:29-4°35. Brittle. 
Composition. Ba O,; C=Carbon 
dioxide 22:3, baryta 77°7=100. B. 
B. decrepitates and fuses easily, 
tingeing the flame green, to a trans- 
fucent globule, which becomes 
Opaque on cooling, and colors a 
moistened turmeric paper red. 
Effervesces in hydrochloric acid. 
Diff. Distinguished by its spe- 
eific gravity and fusibility from calcite and aragonite; its 

