...Gregory R. Lumpkin; Mark G. Blackford; Michael Colella Abstract Davidite (A 1−x M 21 O 38 ) samples from five different geological localities contain approximately 0.2 to 9.5 wt% UO 2 (0.02 to 0.65 atoms per formula unit) and <0.1 to 1.3 wt% ThO 2 (<0.01 to 0.09 atoms per formula unit...

...Don Chipley; Paul A. Polito; T. Kurtis Kyser Abstract Laser-ablation high-resolution inductively coupled plasma mass spectrometry (LA-HR-ICP-MS) is a rapid, accurate, and inexpensive technique for making in situ U-Pb isotopic measurements of uraninite and davidite. The advantages of this method...

...B. M. Gatehouse; I. E. Grey; P. R. Kelly Abstract Davidite from the Pandora Prospect, Pima County, Arizona, crystallizes in the space group R 3 with lattice parameters a = 9.190(3)A, α = 68.73(1)°. Its formula, determined from microprobe analysis, is REE 0.91 U 0.33 Ca 0.20 Y 0.25 (Sr,Th,Pb) 0.09...

.... The structure is based on oxygen closest-packing with, by analogy to the magnetoplumbite structure, Pb in the anion framework. Davidite, which has a unit cell of the same dimensions as that of senaite, has the probable primitive unit cell contents (Ti, Fe, …) 21 O 39 . Copyright © 1968 by the Mineralogical...

...A. Pabst Abstract Partly or wholly metamict davidite from Pima County, Arizona and from Iveland, Norway, has been reconstituted to single crystals or twins by heating in air. The cell dimensions are a 0 10.37 ± 0.02, c 0 20.87 ± 0.02 Å. The space group is R 3 or R 3. The suggested ideal content...

...J. D. Hayton Abstract Reply to a paper by J.D. Hayton (GeoScience Abstracts 2-3024). In addition to showing a peculiar and diagnostic lanthanon distribution, davidites are chemically characterized by 1) a relatively high Sr/Ca ratio combined with a low alkaline earth content, 2) a relatively high U...

...J. R. Butler; R. Hall Abstract "Twelve davidites from several localities and of different parageneses have been analysed for U and individual rare earths. The abundance of the total lanthanons invariably exceeds that of Yt and the distribution of the individual lanthanons is strikingly similar...

...J. D. Hayton Abstract Rather than a heterogeneous mixture of rutile with one or more radioactive constituents, as suggested by A. W. G. Whittle, davidite is considered a homogeneous mineral in which uranium and the lanthanons are isomorphously replaceable, as well as probably Ti, V, Cr, and Al...

...Alick W. G. Whittle Abstract The Precambrian rocks of Australia contain a wider variety of davidites than has been found elsewhere in the world. Investigation of davidite occurrences as an economic U ore over a number of years has revealed its many peculiar physical and chemical characteristics...

... to the davidite from Olary, South Australia, as described by Mawson. The principal metallic elements in the Mozambique mineral are titanium, iron, uranium and chromium. Experimental data further confirm Mawson's original description of davidite as a distinct mineral species. The application of differential...

...L. J. Lawrence Abstract "The davidites, which occur disseminated in Archaean schists and granulites, exhibit a number of interesting microtextures and show a wide variation in U 3 O 8 content. In one instance the uranium content appears to be shared between davidite and ilmenite with which...