ORDER I. RHOMBOHEDRAL FLUOH-HALOIDE. 73 



ritic greenstone. Well defined octahedrons of an apple- 

 green colour at Moldawa, in the Sannat of Temeswar. 

 Hose-red octahedrons are met with near Chamouni in 

 Savoy, associated with tabular crystals of rhombohe- 

 dral Lime-haloide ; emerald-green octahedrons have been 

 brought from America. The Saxon varieties are gene- 

 rally of a hexahedral form, and violet-blue or wine-yel- 

 low colours ; yet there occur some of other forms and co- 

 lours, both in Saxony and the adjacent districts of Bohemia. 

 The compound uncleavable varieties (compact fluor) are 

 chiefly known from Strassberg and Stollberg in the Hartz, 

 Cornwall, and Sweden. The friable ones (earthy fluor) are 

 found in Saxony, England, and Norway. Several parts of 

 Germany, France, Siberia, America, &c. produce likewise 

 varieties of this species. 



5. Octahedral Fluor-haloide, particularly those varieties 

 which consist of columnar particles of composition, are cut 

 and polished for various ornamental purposes. In Derby- 

 shire they are turned into vases, for which, however, they 

 require first to be prepared by certain processes, which in- 

 crease their tenacity. In former times, those of fine co- 

 lours used to be cut and worn as gems, and were designated 

 by the same names. A more important employment is that 

 of fluxing several ores, from which the name of Fluor has 

 been derived. The fluoric acid, disengaged from it by means 

 of sulphuric acid, has been used for corroding and etching 

 upon glass. 



2. RHOMBOHEDRAL FLUOK-HALOIDE. 



Rhombohedral Apatite. JAM. Syst. Vol. II. p. 575. Man. 

 p. 32. Apatite. Phosphate of Lime. PHILL. p. 167- 

 Apatit. Spargelstein. Phosphorit. WERN. Horfm. H.B. 

 III. 1. S. 84. 89. 92. Apatit. Phosphorit. HAUSM. III. 

 S. 869. 872. Phosphorsaurer Kalk. LEONH. S. 557. 

 Chaux phosphate'e. HAUY, Traite', T. II. p. 234. Tabl. 

 comp. p. 7- Traite', 2de Ed. T. I. p. 487- 

 HAIDIXGEB. Edin. Phil. Jouru. No. XIX. p. 140. 



