174 
Teansactions Texas Academy of Science. 
Hillebrand^ W. F. 
UO2 
Th O, 
Zr O 2 
Ce O 2 
La group. 
Y group.. 
Ca O 
Pb O 
Hs O 
N 
SiOs 
Insol 
Fog O3 
I. LLANO COUNTY, TEXAS. 
a h 
HILLEBRAND. HIDDEN AND MACKENTOSH. 
.... 44.17 46.75 
.... 20.89 19.89 
.... 6.69 7.57 
.... 0.34 
.... 0.34 
.... '2.36 
.... 9.46L.... 11.224 ' 
.... 0.32 
.... 10.08 10.16 
.... 1.48 2.54 (ign.) 
.... 0.54 
.... 0.46" 
... 1.473 1.22 
.... 0.14 0.58 
Sp. G. 
98.74 ‘99.93 
8.29 8.01 
1. At. weight, 111.4. 2. Prom thorogummite. 3. Mainly fergnsonite. 
4. At. weJight, 124.2. 
“No. la is a re-analysis of nivenite from Llano county, Texas, the mate- 
rial for which was kindly given hy Mr. W. E. Hidden. It agrees in 
the main with the original analysis of this variety by Hidden and Mack- 
entosh, which is reproduced under 15, and it confirms the presence of 
nitrogen, suspected but not proven hy them. A small remnant of their 
original, powdered sample gave me 0.52 per cent, of nitrogen. In a 
the earths appear in slightly greater total amount than in 5, and they 
are more subdivided into groups and elements, Avhich accounts fully for 
the difference between the atomic weights of the metals of the yttrium 
group of the two analyses. It was rendered certain by a second test that 
a group of earths whose sulphates are insoluble in potassium sulphate other 
than those of Th, Zr, and iCe is present. A very satisfactory turmeric paper 
reaction for zirconia was obtained in this analysis, as also in that next 
following, which would go to ishow that the hypothetical Zr O2 of several 
of my earlier analyses was probably in fact zirconia. The cause of the 
consdderiable loss shown by the analysis is not known. It may be men- 
tioned that nivenite is more soluble than any uraninite heretofore exam- 
ined by me, not even excepting cleveite. One hour sufficed for complete 
decomposition in very dilute sulphuric acid (1 Hg 'SO4 to 6 H2 0) at the 
temperature of boiling water.” 
Of the other specimens analysed. No. 11 is from Marietta, Greenville 
county, iSouth iCarolina; No. Ill from Villeneuve mica mine, Ottowa county. 
Province of Quebec, Canada, and No. IV from Johanngeorgenstadt, Saxony. 
252. 
See HiddieU; W. E. On Mackentosliite, ,a new tbo-rinm and nran- 
inm mineral, with analyses by W. F. Hillebrand. 
Amer. Jonr. of Science, III, Vol. XLVI, pp. 98-103. New 
Haven, Aug., 1893. 
