TAB. XCVIII. 



BARYTES sulphata. 

 Sulphate of Barytes. 



Class 1. Earths. Order 1. Homogeneous. 

 Gen. 6. Barytes. Spec. Sulphate. 



Div. 1. Crystallized. 



1 he specimen from which this figure was taken is in the 

 collection of Mr. Professor Hailstone at Cambridge, to 

 whom it was presented by John Probart, Esq., of Cop- 

 thorne near Shrewsbury, in whose interesting museum the 

 Professor saw several other crystals of the same kind, but 

 of larger dimensions, and understood that they were found 

 in some part of Shropshire; but he had no opportunity 

 of ascertaining any further particulars respecting their 

 native beds, and situation in the earth. 



It is a valuable specimen, to show the nature of a crystal 

 terminated on all sides, and independent, or not fixed on 

 any gangue. This is not common to sulphate of barytes. 

 It has only a few quartz crystals at the upper corner, as 

 expressed in the figure. The modification is altogether 

 singular, and is a variety not yet figured ; we find it has 

 23 faces, some scarcely distinct. The crystal is lengthened 

 parallel to the obtuse angles of the rhomb, and the upper 

 primitive face, which shows the prismatic hues somewhat 

 below the surface. It has little hollows as it were unsup- 

 plied by molecules 3 this is the case also in other parts^ 



R 2 



