3©© Count de Bournon on Bardiglione, 



Bardiglione of a determinate Figure. 



The crystalline state is that in which this substance most commonly 

 occurs ; but its forms are seldom determinate. The finest crystals, 

 and the greatest variety, have been found in the mine of rock-salt at 

 Hall in the Tyrol; which is also the place where it has been most 

 commonly observed of a determinate crystalline figure. The crystals; 

 occur there in groups, either colourless, or of a pale red slightly 

 inclining to violet. They are commonly pretty large, frequently 

 flattened, and often of very little thickness. They intersect each 

 other in different directions, and very often several are joined toge- 

 ther so as to have the appearance of a single crystal : but in these 

 cases their lines of separation are readily perceivable ; and, asthey 

 adhere together but slightly, they are easily separated. Sea-salt is 

 frequently found disseminated through these crystals ; and in this 

 case, the same salt very often also shews itself externally in small 

 distinct masses, which are easily known by their inferior lustre and 

 hardness. When the Abbe Poda first noticed these substances, it 

 was the variety of Hall that came under his observation. The sea- 

 salt, of which there are frequently considerable masses in it, led him 

 to consider it as a mixture of this salt, with gypsum. Its rectan- 

 gular figure also contributed to this error, which made him give it 

 the name of Muriacite. 



In 1802, when Mr. Chenevix analysed this variety of bardiglione 

 from Hall, at my request, the person employed in pulverizing it found 

 some small needles of antimony included in the interior of one of 

 the crystals, most of them adhering to small groups of crystals of 

 quartz ; and to prevent all dispute about it, he preserved a fragment 

 of the crystal, to which one of these needles still adhered. This fact. 



