54 BREUNNEEIT. . 



the Island of Unst, in Shetland, where it 

 occurs in small yellowish-brown crystals, 

 imbedded in green foliated Talc, at the head 

 of Norwick Bay. 



Named by Haidinger, in compliment to 

 Count Breunner. 



Brit. Mus., Case 49. 



Breunnerit, Haidinger, Hmismann ; or 

 Bbeunnerite, NicoL Native carbonate of 

 Magnesia. See Magnesite. 



Brevicite occurs in transparent colour- 

 less prisms, and white, laminar, radiated 

 masses, which are sometimes marked with 

 striae of a dark-red hue. 



Comp. 2 Na Ca, 2 ll, 5 Si, 4 H. 



Analysis from Stroni, bv Souden : 

 Soda . . . ' . . 10-32 



Lime 6-88 



Magnesia . . . .0-21 

 Alumina .... 28-39 



Silica 43-88 



Water . . . . . 9-63 



99-31 



Locality. Brevig in Norway (whence 

 the name Brevicite). 



Brit. Mus., Case 28. 



Bre \v ST KBIT, Haidinger, Hausmann, Nau- 

 mann,v. Kohell; Brewsterite, Greg 8f Lett - 

 som, Phillips, Beudant. Oblique. Primary 

 form an oblique rectangular prism. In small, 

 greyish- white, or yellowish crystals, with a 

 vitreous lustre, except on the faces of 

 cleavage, which are pearly. Transparent 

 to translucent. Streak uncoloured. Brittle. 

 Fracture uneven. H. 3-5 to 4. S.G. 2-09 

 to 2-16. 



r^;S3\ 



Fig. 64. 



Comp. (Sr, Ba, Ca) Si + M bi3 + 5H. 



Analysis by Thomson : 



Silica 53-04 



Alumina . ._ . .10-54 

 Baryta . .' . .6 05 



Strontia . . . .9 01 



Lime 0-80 



Water . , . . . 14 73 



BROCHANTITE. 



With salt of phosphorus melte easily, leav- 

 ing a skeleton of silica. 



Soluble in acids, leaving a residue of 

 silica. 



Brewsterite was first discovered at Stron- 

 tian in Argyleshire, where it occurs in small 

 translucent crystals, both colourless, and 

 of a brownish tinge, generall}'- associated 

 with Caicite. It is found, also, at the 

 Giant's Causeway, lining cavities in amyg- 

 daloidal rocks; in the lead mines of St. 

 Turpet ; near Freiburg in the Brisgau ; in 

 the department of the Isere in France, and 

 in the Pyrenees. 



Named after Sir David Brewster, 

 hrit. Mus., Case 28. 



Brewstoline, Dana, a transparent, co- 

 lourless fluid detected by Sir David Brew- 

 ster in Siberian Amethyst. It also occurs 

 in minute cavities in crystals of Topaz, 

 Chrysoberyl, Quartz crystals from Quebec, 

 and in blue Topaz from Aberdeenshire. The 

 fluid expands one-fourth its size by an in- 

 crement of 30° F., or is nearly thirty-two 

 times more expansible than water, by a 

 change of temperature from 50° to 80° 

 Brewstoline is stated by R. T. Simmlen 

 to be liquid carbonic acid. 



Name. After Sir David Brewster, by 

 whom the first accurate researches were 

 made into the nature of the liquids and 

 gases which occur in the cavities of Quartz, 

 &c. 



Brick-red Copper Orb, Kirwan. See 

 Tile -ORE. 



Bright White Cobalt, Kirvmn, Phil- 

 lips. See Cobaltine. 



Brittle SilvebGlance,"^ 

 Jameson. j 



Bbittle Silver Ore, ! See Stephan- 

 Allen. I ITE. 



Brittle Sulphuret of | 

 Silver, Phillips. j 



Broad foliated Gypsum, Kirwan, See 

 Selenite. 



Broc'HANtite, Greg 8f Lettsom. Rhom- 

 bic. Primary form a right rhomboidal 



100-17 



BB loses its water, becom.es opaque, and 

 then froths and swells, but does not fuse. 



Fig. 65. 



prism. Occurs in small, well-defined, trans- 

 parent crystals of an emerald-green to a 

 blackish-green colour, having a vitreous 



