METHOD OF OBTAINING ZIRCON.

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It melts with borax into a transparent colourless glass. It suffersin a charcoal crucible a pasty fusion by intense heat, and contractsin its dimensions, acquiring a grey colour and scintillating hard-ness. In this state it is very hard and insoluble in acids. Itsspecific gravity is 4.3. Neither air nor combustible bodies actupon it. It is soluble in water, but retains while drying in theair a large quantity of it, which gives it die semi-transpa-rency and appearance of a yellow jelly, or gum-arabic; it exhi-bits the same vitreous fracture. It unites with all the acidsand forms salts, differing from those of the other bases by beingdecomposable by alumine, glucine, the alcalies, and by mere heat.It fuses with alumine and silex. It is insoluble even by boilingin a solution of alcalies, neither can it be fused with them bymeans of heat; but it is soluble in alcaline carbonates.

By these properties this earth may be distinguished from everyother. It is still of no use in the arts.

METHOD OF OBTAINING ZIRCON.

Reduce the mineral to powder, mix it with three times itsweight of potash, and fuse it in a crucible. Wash the obtainedmass in distilled water, till the whole of the potash be extracted;then dissolve the residuum as far as possible in diluted muriaticacid. Boil the solution to precipitate any silex it may contain,filter it, and gradually add solution of potash. The zircon willnow become precipitated. Wash it repeatedly in distilled waterand dry it.

*Vuv,.

VOL. II.

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