lOG LieuL Badddey on Sulj^hate of Strontmi^ ^-c 



a lighted candle, a portion of the flame will become of a beautiful 

 rose-red color; and it is this character which peculiarly distinguishes 

 this mineral from the sulphate of barytes. Its sp. gr. is also less. 

 Several attempts to develop the rose color, by dropping gradually 

 the powder of tliis mineral into inflamed spirhs of wine, as directed 

 by some authors, were unsuccessful. It is insoluble in sulphuric 

 acid, in which, according to Griffin, sulphate of barytes is soluble. 

 Before the blowpipe on charcoal, it fuses slowly in the interior 

 ilame, into a dull white enamel ; this enamel, when cold, has a 

 slight hepatic odor, and a very nauseous flavor, like a mixture of 

 rotten eggs and caustic lime. When the platina forceps are used, the 

 enamel produced is shining and pearly, and the hepatic flavor is not 

 perceived."^ With borax on charcoal (after roasting) it effervesces 

 and forms a glass, which, when cold, is of a reddish brown or yel- 

 low color. 



The characters in which this mineral appears to differ from those 

 described by different writers, as belonging to sulphate of strontian, 

 are two in number, viz. : — 1st. Sulphate of strontian is described by 

 Griffin as decrepitating in the exterior flame of the blowpipe. Nei- 

 ther Phillips nor Cleaveland, however, mentions such a character as 

 belonging to celestine. Berzelius, who appears to be Griffin's au- 

 thority, says, that "the crystallized mineral decrepitates." The 

 iftineral in question has not tlie least disposition to decrepitate with 

 heat. 2nd. Berzelius also describes sulphate of strontian as yield- 

 ing a globule of enamel in the interior flame of the blowpipe, which 

 communicates to tlie palate a caustic and hepatic flavor ; charac- 

 ters agreeing precisely with those of the mineral under examination : 

 now Cleaveland makes the hepatic flavor a distinguishing character 

 between sulphate of barytes and sulphate of strontian, to the former 

 of which minerals, according to him, that character belongs, and not 



to the latter. 



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* Query, (I>y the author,) — Joes the presence of the metal prevent the formation 

 of the sulphuret ? Answer — the presepce of the charcoal is essential ; it acts by de- 

 taching the oxygen of the sulphuric acid, and leaving the sulphur in combination 

 with the base ; of course, the platinum support, not attracting oxygen, cannot pro- 

 duce this change- It is however much more remarkable in the case of sulphate of 

 barytes than of strontites, but it is exhibited by both. It may be observed also that 

 both sulphates in fine powder, are soluble in a large excess of strong sulphuric acid, 

 and that water precipitates both hy attracting the acid, which holds the dissolved 

 Sulphates by a feeble affinity. — Editor. 



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