MINERALOGY. ' 305 



arranged with reference to one another as are quartz and feldspar in 

 schrift granite, and, as in this case the mineral intermingled with 

 the feldspar is hexagonal. *In composition it is somewhat related 

 to muscovite or nephelin. It is white and fibrous, and only detected 

 by microscopic examination. Named from su, well, and /.pu-rdq, con- 

 cealed. 



Etiralite. — A dark-green chloritic substance, resembling delessite, and 

 found by F. J. Wilk, at Eura Kirchspiel, Finland. 



Fairfieldite. — An hydrous manganese calcium phosphate, found by Brush 

 and Dana, at Branchville, in Fairfield County, Connecticut. It is a 

 colorless and transparent mineral with a good cleavage, and triclinic 

 in crystallization. 



Filloicite. — A mineral found by Brnsh and Dana at Branchville, and 

 named after the owner of the property on whose land they explored. 

 Occurs in granular and crystalline grains, the latter looking like 

 rhombohedrous but really monoclinic in form. It is a manganese 

 phosphate containing a little iron and soda, and of a wax-yellow color. 



Fredricite. — A mineral related to tetrahedrite, but contains lead and 

 tin. It is found in massive, iron-black pieces, at the Fain mine, 

 Sweden, and is chiefly composed of copper, sulx)hur, and arsenic. 

 Described by Hj. Sjogren. 



Gelatinous eliabazite. — Eenevier found a gelatinous substance in fissures 

 in the conglomerate near Lausanne, Switzerland, that had the com- 

 position of chabazite. He called it a mineral in embryonic condition. 

 This was inappropriate, because no such condition is possible in the 

 organic kingdom. A mineral is complete as soon as formed, and 

 its crystalline condition is one of its essential properties. This is a 

 new mineral if its composition is definite. 



Guejarite. — A copper antimony sulphide, fouud by M. E. Cnmenge in a 

 vein of spathic iron, at Guejar, in the Spanish Sierra Nevadas. Oc- 

 curs in bright crystalline plates, that are sometimes quite large. It 

 is quite heavy, is steel-gray in color, and of rhombic crystallization. 



Hannayite. — A hydrous magnesium ammonium phosi^hate found in the 

 guano beds at Victoria. It was determined and named by vom Eath, 

 and found to be triclinic in crystallization. 



Haughtonite. — A black mica, which was taken out of gneiss from Eoneval, 

 and analyzed by Heddle. It is intermediate between biotite and lepi- 

 domelane, and consequently scarcely needs any new name. 



Meldhurgitc. — Another mineral of unknown composition, but iiossessing 

 angles like those of Zircon. It is a yellow mineral seen in the feldspar 

 of phonolite from Heldburg in Colburg, by O. Luedecke. 



Serrengrundite. — A basic copper sulphate from Herrengrund, Hungary. 

 Occurs in six-sided tabular crystals of the monoclinic system. In 

 color it is dark emerald green. Occurs mixed with gypsum, malachite, 

 and calcite. (See urvolgyrite.) 

 S. Mis. 31 20 



