Temperature of Sublimation, 



859 



Table I. 



1. 



<2 



3. 



4. 



5. 



6. 



7. 



8. 



9. 

 10. 

 11. 

 12. 

 13. 

 14. 

 15. 

 16. 

 17. 

 18. 

 19. 

 20. 



Stibnite. Sb 2 S 3 . 



Chalcostibite. Cu 2 S, Sb 2 S 3 . 

 Tetrahedrite. 4 (Cu 2 S), Sb,S 3 . 

 Zinkenite. PbS, Sb 2 S 3 . 

 Jamesonite. 2 PbS, Sb 2 S 3 . 

 Geocronite. 5 PbS, Sb 2 S 3 . 

 Plagionite. 5 PbS, 4 Sb 2 S 3 . 

 Boulangerite. 5 PbS, 2 Sb 2 S 3 . 

 Frieslebenite. 5 (Pb, As) S, 2 Sb 2 S 3 . 

 Bournonite. 3 (Pb, Cu 2 ) S, Sb 2 S 3 . 

 Miargyrite. Ag 2 S, Sb 2 S 3 . 

 Stephanite. 5Ag 2 S, Sb 2 S 3 . 

 Polybasite. 9Ag 2 S, Sb 2 S 3 . 



Berthierite. FeS, Sb 2 S 3 . 

 Oylindrite. 6 PbS, 6 SnS, Sb 2 S 3 . 

 Livingstonite. HgS, 2 Sb 2 S 3 . 



21. Breithauptite. NiSb. 



22. Corynite. Ni(As, Sb)S. 



23. Dyscrasite. Ag 3 Sb. 



24. Allemontite. SbAs 3 . 



25. Antimony, native and prepared. 



Auvergne 475 



Transylvania 490 



Loc. ? 490 



Iyo, Japan 470 



Wolfsberg 475 



Loc? 475 



Wolfsberg 475 



Cornwall 480 



Sala 450 



Wolfsberg 475 



OberLahr 495 



Guanajuato 480 



Liskard 490 



Brausdorf 500 



Schemnitz 490 



Loc? 495 



Guanajuato 430 



Brausdorf 550 



Bolivia 600 



Huitzuco 440 



St. Andreasberg 500 



Siegen 490 



Baden . 520 



Allemont 400? 



500 



The oxide appearing at the temperatures recorded in the 

 table is in general, if not always, the oxide Sb 4 6 . The 

 oxide Sb 2 4 appears at a somewhat higher temperature. 

 In many cases there is a definite cessation of sublimation 

 between the appearance of the two oxides as the tempera- 

 ture is raised. The interval may be 60 degrees or more ; 

 varying considerably. I have only incompletely examined 

 this phenomenon. 



The most interesting feature of the table is the remarkable 

 uniformity of temperature of sublimation of the minerals 

 examined. Nos. 18 and 19 show rather unusually violent 

 deflagration close to the sublimation temperature. This 

 phenomenon seems generally attended by an exceptionally 

 high sublimation temperature. It probably arises from 

 superheating above the normal temperature of decomposi- 

 tion ; the deflagration ensuing on a sudden breakdown of 

 equilibrium. The decomposition of the stibnite molecule 

 of No. 20 is preceded by the evolution of a sublimate of 

 mercury. The temperature of subliming of the antimony is, 



