Hidden and Mackintosh — Sodium sulphato- chloride. 463 



direct bearing upon the presence of thorium in monazite, and 

 we believe that the idea that thorium is included in monazite 

 as thorite — mechanically intermixed — should be modified in so 

 much that the thoria should be considered as partially present 

 as a phosphate and the cerium earths partially present as sili- 

 cates. 



This mineral is readily soluble in hydrochloric acid, leaving 

 a residue of gelatinous silica ; after ignition it becomes insoluble. 

 Thorium phosphate is generally regarded as a very insoluble 

 compound, but the ready solubility of this mineral seems to 

 disprove that opinion. 



It is infusible and upon strong ignition becomes dull-brown 

 and on cooling, orange again. 



Thorite crystals having the form of zircon have been de- 

 scribed by Zschau ;* and Nordenski6ld,f and later Bro'gger,^ 

 have expressed the opinion that the mineral known as thorite is 

 a pseudomorph after an original thorium silicate analogous to 

 zircon in composition. This view is confirmed by the fact that 

 this new mineral occurs intimately associated with and implanted 

 upon perfectly unaltered zircon. 



As this mineral was found while mining the very large quan- 

 tity • of zircons necessary to supply the demand caused by the 

 invention of the system of incandescent gas-lighting of Dr. 

 Carl Auer von Welsbach, we propose to name it Aioerlite in 

 his honor. 



Art. XLIX. — On a new Sodium sulphato-chloride, Sulpho- 

 halite ; by W. E. Hidden and J. B. Mackintosh. 



It was in the mineral collection of Mr. Clarence S. Bement, of 

 Philadelphia, and along with a series of remarkable crystals of 

 hanksite that one of us first noticed the mineral here described ; 

 it was recognized by a few simple tests to be a new species. 

 It had been considered, at the locality, to be " a rhombohedral 

 type of hanksite " and the misinterpreted form of its crystals 

 — implanted as they were upon hanksite — was the reason for 

 that opinion. A few measurements with a hand goniometer 

 soon showed them to belong to the isometric system and the 

 form to be the simple rhombic dodecahedron. The mineral 

 occurs only as crystals, which are in form and sharpness of an- 

 gle, all that could be desired. It is transparent with a faint 

 greenish-yellow color. The crystal faces are smooth and well 

 polished and vary in size from -| to 2J cm diameter. The spe- 



* This Journal, II, xxvi, 359; see also Dana's Syst. Min., Ed. 1868, p. 413. 

 f Geol. For. Forh., iii, 226, 1876; see also App. Ill, Dana's Min., p. 121. 

 % Ibid, ix, 258, 1887. 



