EDENITE. 





Edenite, Breithaupt. 



A whitish alu- 



minous Hornblende, from Edenville, in the 



United States. S.G. 3-059. 





Analysis by Rammehberg 





Silica . 



. 61-67 



Alumina 





. 5-75 



Peroxide of iron 





: 2-86 



Lime . 





. 12-42 



Magnesia 





. 23-37 



Soda . . 





. 0-75 



Potash . 





. 0-84 



Loss by ignition 





. 0-46 



98-12 

 Edingto>:it, Haidinger, Hausmann, Nau- 

 mann ; Edingtonite, Dana, Phillips, Greg §• 

 Lettsom. Pyramidal, hemihedral : primary 

 form an octahedron, with a square base. Oc- 

 curs in extremely distinct, greyish-white, 

 translucent crystals, none of which are known 

 to exceed fths of an inch across. Lustre 

 vitreous. Streak white. Brittle. Fracture 

 imperfect-conchoidal, uneven. H. 4 to 4-5. 

 S.G. 2-69 to 2-71. 



Fig. 171. 



Fig. 172. 



Comp. 3 Ba Si+4Al Si-fl2 H = silica 

 37-263, alumina 23-751, baryta 26-524, Avater 

 12-462-100. 



Analysis by Heddle : 



Silica 36-98 



Alumina .... 22-63 



Barvta 26-54 



Lim^e .... 0.22 



Strontia . . . .0 08 



Soda trace 



Water 12-46 



98-91 



BB fuses with difficulty to a colourless 

 glass, after having given off water, and be- 

 come white and opaque. 



Locality. This rare mineral is met with 

 near Old Kilpatrick, in Dumbartonshire, 

 and is named after Mr. Edington, by whom 

 it was first discovered in 1823. 



Brit. Mus., Case 28. 



Edler Opal, Werner. See Precious 

 Opal. 



Edwardsite, Shepard. A variety of 

 Monazlte. Occurs in oblique rhombic prisms. 

 Colour hyacinth-red. Transparent to trans- 



EGYPTIAN PEBBLE. 121 



lucent. Lustre vitreous to adamantine. 

 Streak white. H. 4-5. S.G. 4-2 to 4-6. 



Fig. 173. 



Comp. Sesquiphosphate of cerium. 



Analysis : 



Protoxide of cerium . . 56-53 

 Phosphoric acid . . . 26-66 

 Zirconia .... 7-77 

 Alumina . . .* . 4-44 



Silica 3-33 



Glucina, magnesia, protoxide 

 of iron .... traces 



98-73 

 BB in minute fragments, loses its red 

 colour, and becomes pearl -grey, with a tinge 

 of yellow, and fuses with difficulty at the 

 edges to a transparent glass. 



In a powdered state slowlj' soluble in aqua- 

 regia. 



Locality. Disseminated through Buchol- 

 zite, in gneiss, at the falls of the Yantic, in 

 Norwich, Connecticut, U. S. 



Name. After Henry W. Edwards, governor 

 of the State. 

 Brit. Mus., Case 57. 



Efflorescent Zeolite. Aname formerly 

 given to Laumontite, in consequence of its 

 efflorescing, and becoming opaque and crum- 

 bling on exposure to the air, probably owing 

 to the loss of water. 



Egeran. a variety of Idocrase, of a 

 liver-brown colour, occurring in diverging 

 groups of crystals, whose form is that of a 

 right rectangular prism, having its lateral 

 edges replaced. 



Analysis, by Karsten : 



Silica 39-70 



Alumina .... 18-95 

 Protoxide of iron . . . 2*90 



Lime 34-88 



Protoxide of manganese . 0-96 

 Soda 2-10 



99-49 



BB fuses with intumescence to a greenish 

 blebby glass. 



Localities. Haslau, near Eger (whence the 

 name Egeran), in Bohemia ; sometimes ac- 

 companied by Quartz and Tremolite. 



Brit. Mus., Case 35. 



Egyptian Jasper; Egyptian Pebble. 

 A variety of Jasper occurring in roundish 

 pieces scattered over the surface of the 

 desert, chiefly between Cairo and the Red 

 Sea. The surface of these masses is rough. 



