PHYSIOGRAPHY. 



Allanite. 



1. Several minerals, proposed by different authors as distinct, appear 

 to fall within the present description. Of these the Allanite of THOM- 

 SON presents us with the most distinct crystals. The Orthite of BER- 

 ZELIUS owes its diminished sp. gr. to its state of partial decomposition. 

 The Cerine of the same author, or the Cerium oxide siliceux noir of 

 HAUY, is usually compact and black. 



2. Allanite froths before the blow-pipe, and melts imperfectly into a 

 black scoria, and it gelatinizes in nitric acid. Orthite froths, becomes 

 yellowish brown, and melts with effervescence into a black vesicular 

 globule; with borax into a transparent one, and gelatinizes in heated acids. 

 The Cerine behaves in a similar manner, but Us globule acts upon the 

 magnetic needle. 



3. Analysis. 



4. Allanite was first found at Alluk in East Greenland, accompanied 

 by Zircon and Quartz. Orthite occurs at Finbo, near Fahlun in Swe- 

 den, along with Quartz, Feldspar and Albite, in gneiss. The Cerine ex- 

 ists in the copper mines of St. Gorans at Riddarhytta. 



ALLOCHROITE. (See Garnet.) 



