372 TALKSPATH, 



TalkspATH, Hartmann, Naumann. Na- 

 tive Carbonate of Magnesia. See Magne- 

 siTK. The name Talkspath is also used by 

 G. Rose and others for carbonate of mag- 

 nesia-and-iron (Bitter Spar and Brown Spar 

 in part). See Breunnerite. 



Talksteinmark. See Myelin. A va- 

 riety of Lithomarge, from Rochlitz in Saxony. 

 TajMARIte, Greg ^ Lettsom. The name 

 proposed by Brooke and Miller for Copper- 

 Mica (Chalcophyllite), from its occurrence, 

 amongst other localities, at Huel Tamar. 



Tammela-tantalite. a variety of Tan- 

 talite, from Tammela, in Finland, containing 

 only a small quantity of tin. Colour black. 

 Lustre submetallic. Streak blackish -brown 

 to cinnamon-brown. S.G. 7-311 to 7*943. 

 Analysis, by Weber : 



Tantalic acid . . . 83-90 

 Oxide of tin ... 0-66 



Protoxide of iron . . 13'81 



Protoxide of manganese . 074 

 Oxide of copper . . .0-11 



99-22 

 See Skogbolite and Tantaltte. 

 Tankite See Chiastoi.itb. 

 Tannenite, Dana. A sulphide of bismuth 

 and copper, occurring in thin striated prisms, 

 of a colour varying from greyish to tin- 

 white, with a bright metallic lustre. 

 Comp. -euSfBiSSS. 

 Analysts, by R. Schneider : 



Sulphur .... 18-83 

 Bismuth . . . .62-16 

 Copper .... 18-72 



99-71 

 BB on charcoal, swells up and fuses 



readily ; with soda yields a globule of copper. 



With nitric acid forms a deep bluish -green 



solution, which becomes dark blue on the 



addition of ammonia. 



Locality. Tannenbaum, near Johanngeor- 



genstadt in Saxony. 



Tantale Oxide, Haiiy. See Columbite. 



TaNTALE oxide FERRO-MANGANESIEiRE, 



Haiiy. See Columbite. 



Tantale Oxide Yttrifere, Haiiy. Se« 

 Yttrotantalite. 



Tantalate of Iron. See Tantalite. 



Tantalite, Eckeherg, Jameson, Phillips. 

 Rhombic : primary form a right rectangular 

 prism. Occurs in single crystals and in 

 small crystalline masses; the crystals are 

 mostly incomplete, but posseSs the general 

 form of quadrangular prisms, striated longi- 

 tudinally, and variously modified. Opaque. 

 Colour iron-black, vt^ith a nearly^ure me- 



TANTALITE. 



tallic lustre. It scratches glass and gives 

 sparks with steel. Streak reddish-brown, or 



Fig. 422. Fig. 423. Fig. 424. 



coffee-coloured. Brittle. Fracture uneveri 

 or conchoidal. H. 6 to 6*5. S.G. 7-1 to 7-96. 



Comp. (Fe Mn) (fa Cb). 



Analysis, from Kimito, by Weber : 

 Tantalic acid . . . 75-71 

 Oxide of tin ... 9-67 



Protoxide of iron . . 9-80 



Protoxide of manganese . 4-32 



99-50 

 BB alone, unchanged : with borax, the 

 varieties containing large proportions of 

 tantalum dissolve slowly but perfectly, im- 

 parting to it a faint green colour. Those with 

 less tantalum fuse readily to a black or dark 

 green glass, which is nearly opaque. 

 Partly soluble in heated sulphuric acid. 

 Localites. — Finland : at Skogbole, in the 

 diocese of Kimito, and Harkasaari in that 

 of Tammela; also at Bjortboda. 



The metal Tantalum was discovered by 

 Eckeberg, in specimens from Kimito. 



The tantalites from Finbo and Broddbo, 

 as well as some of those from Kimito con- 

 tain a large quantity of oxide of tin (see 

 Cassiterotantalite), and in those from 

 the latter locality, part of the iron is re- 

 placed by manganese. Tantalite was first 

 found in America, at Kaddam, in Connecti- 

 cut : it also occurs at Bodenmais in Bavaria, 

 associated with Beryl, and remarkable for 

 containing niobic acid ; likewise in France, 

 at Chanteloube near Limoges. 



The two first localities are properly for 

 Columbite (which see). The following is an 

 analysis by Jenzsch from Chanteloube, (S.G. 

 7-703) which is Tantalite proper. 



Tantalic acid . . . 83-55 

 Oxide of tin ... 1-02 



Zirconia .... 1*54 

 Protoxide 0* iron . . 14-48 



Oxide of manganese . . trace 



100-59 



The name Tantalite was restricted by 



Nordenskiold to the varieties containing 



only a small quantity of oxide of tin, from 



Tammela, Bjortboda and Kimito in Fin- 



