131 



TAB. CCCLXX. 



CALX carbonata. 

 Carbonate of Lime, 



Div. 1. Crystallized. 



5yn. Chaux carbonatee contractee. Haiiy, 2. 143. 



A rare modification of Carbonate of Lime from Derby- 

 shire. The faces of the column being alternately broader 

 and narrower at the ends would, if extended, make an 

 acute rhomb, formed by a slight deviation from the law by 

 which the regular hexhaedral prism is produced. The apex 

 is formed by three faces corresponding with those of the 

 equiaxed rhomb, tab. 13 and 128, rendered pentagonal, and 

 contracted as it were into narrow facets, by the broader 

 ends of the columnar faces which approach the axis in the 

 direction of the edges of the rhomb ; whence Haiiy's name. 

 It is generally found more or less covered with a brown 

 crust, and has a roughish aspect given it by a mixture of 

 earthy Oxide of Iron. 



The lower figure is less acute, and has also the equiaxed 

 termination : this also is rare, and is coloured a little. 

 Both are upon tabular Sulphate of Barytes. 



L 2 



