At Cooglegong, in _Western Australia_, the uranium mineral fergusonite and to a less extent the uranium mineral euxenite occur in the surface detrital material of the region. At Wodgina the minerals mackintoshite, thorogummite and pilbarite, all hydrous silicates of uranium, thorium and lead, occur in an albite pegmatite dike. No important quantities of these Western Australia ores have yet been produced. =India and Africa.=--Radium and uranium minerals have been reported in _India_ and _German East Africa_, but no important quantities have yet been produced. PROSPECT OF FUTURE DISCOVERIES OF RADIUM AND URANIUM ORES The prospect for increased discoveries of radium and uranium minerals at the present time seems best in the carnotite regions of Colorado and Utah. The workable deposits seem to be more or less superficial, and perhaps no large quantity of ore may be found in any one spot, yet the great extent of the region in which the formations carrying carnotite occur, will supply an immense aggregate amount of ore. Increased discoveries of uraninite, pitchblende and other uranium minerals in Europe seem possible, even though that continent has already been well explored for them. Moreover, new discoveries of different radium and uranium minerals may very likely be made in still other parts of the United States than those mentioned, and in less explored parts of the world, especially certain regions of South America, Australia, Asia and Africa. Many of these minerals, especially pitchblende, have no very distinctive features when first observed, and might readily be overlooked many times before their true nature was discovered. Hence the possibilities of future discoveries. CHAPTER XII ZIRCONIUM BY H. C. MORRIS USES OF ZIRCONIUM As early as 1830 an attempt was made to use zirconia buttons, heated to incandescence, for lighting the streets of Paris. In 1885 an incandescent gas mantle of zirconium oxide was patented, but was replaced in a few years by thorium. About 1900 zirconia was used in the Nernst glower, and it has also been used in place of lime and magnesia as the incandescing material in the Drummond light. It is also said to be used in the Bleriot light, and its use in flares has been suggested.