154 J. M. Davison — Wardite : a New 



Aet. XYIII. — Wardite : a New Hydrous Basic Phosphate 

 of Alumina ; by John M. Davison. 



[Read before the Rochester Academy of Science on April 28, 1896.] 



In the number of this Journal for April, 1894, Mr. Packard 

 describes and gives the analysis of massive variscite from 

 Utah. Since then a considerable quantity of this mineral has 

 been received by Ward's J^atural Science Establishment, of 

 Eochester, ]N^. Y. It is in form of nodules and shows the 

 mineral in several shades of green, and one specimen of pure 

 milk-white color. Nearly all have the firm brownish-yellow 

 outer coating and some show the variscite, altered to a softer 

 whitish mineral, as described by Mr. Packard. 



Occasionally decomposition of the variscite has left cavities 

 in the nodules, and encrusting these cavities is an hydrous 

 basic phosphate of alumina, which does not appear to have 

 been hitherto described. It is of light green or bluish-green 

 color, with vitreous luster, concretionary structure, hardness 

 greater than variscite,— about 5 — and specific gravity 2'77. 

 Its concentric habit has, in places, developed an oolitic struc- 

 ture, resembling clusters of fine shot with rough surface. Tiny 

 balls are found on the surface of the larger masses. A thin 

 section shows that they have been buried in the mineral at all 

 stages of its growth, giving a mottled appearance to the sec- 

 tion. 



Analysis of this mineral gate : 



P,0, -- 34-46 



FeO.. - 0-76 



CuO 0-04 



MgO 2-40 



Na,0 - - 5-98 



K,0 0-24 



H,0 17-87 



Al^Og (by difference) 38-25 



100- 



The formula may be written : P,0,.2A1,03.4H,0, or Al, 

 (0H)3P0, + iH,0, or perhaps AlNaPO,.Al (0H)3.i-H,0. 



This mineral, to which I would give the name of Wardite^ 

 in honor of Prof. • Henry A. Ward, of Rochester, N. Y., 

 would seem to come in series with 



Peganite, A1,(0H)3P0, 4- \\^fi 

 Turquois, A1,(0H)3P0^ 4- H,0 

 Wardite, A1,(0H)3P0, -F ^H^ 



