276 ANALYSES OF ROCKS AND MINERALS, 1880—1908. 
ROWLANDITE. 
From Llano County, Texas. Analysis by W. F. Hillebrand, with discussion in 
Bull. 113. Sp. gr., 4.513 at 15.5°. 
1.62 
+28 
+24 
34 
LazO3 group, mol. wt., 336.8...............- O84 ls a veges a: stieicetin sik miele eeened cues Beige 3. 87 
Yt2O3 group, mol. wt., 266.2... . : 
Fe203 tp age ue ee ah i ar anc ph eta 
PCO) ces ssahuavecucsusins seeeeereces 
Mi Ore cereenecaasecceonc scenes 
C8 Oe Ssscmuarssnawietistsecs¥ a cschce deamiseesecin 
MACKINTOSHITE. 
From Llano County, Texas. Analyzed by W. F. Hillebrand and discussed in Bull. 
113. Sp. gr., 5.43 at 21.4°. Only nine-tenths of a gram available for analysis. 
0.59 
10 
+42 
. 68 
67 
LazO3 group \ 1:86) TeO 86-100"... oescacyeed eyencceye rs eeaeeees 50 
Yt2O3 group HeO above: 100°...055 exsevecoeasas ered geaees 4.31 
PbO wsiscseceveveusecszesess 3.74 
LOA eee Ron ee an are meted L15 96-50 
CYRTOLITE. 
A doubtful mineral from Devils Head Mountain, Douglas County, Colorado. Analy 
ses by W. F. Hillebrand, with description in Proc. Colorado Sci. Soc., vol.3, pt.1, p. 44. 
Brown crystalline growths of irregular form. Sp. gr.: A, 3.70; B, 3.60; C, 3.64. The 
material may be a mixture of cyrtolite or some analogous alteration of zircon with 
limonite and a phosphate. 
¢ A mixture of indefinable earths with some uranium and a trace of titanium. 
