452 Scientific Proceedings, Royal Dublin Society. 



Tantalite (Broddbo, Sweden, 1765) : — possibly rounds at 1240 and melts fairly 



easily at 1315, but less easily than the specimen from Copenhagen. 



The glass shows typically the colour-changes described. 

 Tantalite (Finbo, Finmark, 1767) : — turns grey on heating, and reddens 



litmus. Possibly rounds with signs of sublimation at 1290, and 



flows in iridescent films at about 1450. 

 Tantalite (Middletown, Connecticut, 1764) : — shows signs of rounding with 



sublimation at about 1250, melts at 1340, and flows very freely with 



iridescence at 1410. Fusion tends to acicular crystallization on cooling. 

 Tantalite (Kimito, Finland) : — fuses to a black glass at about 1470, which 



shows incipient crystallization on cooling. 

 Tantalite (Copenhagen, 1766) : — reddens litmus, and melts easily at about 



1210 to a glass which shows colour-change on heating. 

 Tttrotantalite (Ytterby, Sweden) : — reddens blue litmus paper, whitens and 



shows signs of sublimation at about 1255. Melts with iridescence and 



flows at 1375. 

 Tttrotantalite (Ytterby, Sweden, 1771) : — reddens blue litmus paper, whitens 



and shows signs of sublimation. Melts with iridescence and flows at 



1315. 

 Tttrotantalite (Finbo, Sweden, 1769) : — reddens blue litmus, and whitens at 



about 1300. Melts with iridescence and flows at 1430. 

 Samarskite (Mitchell Co. Carolina) : — powder, which is easily distinguishable, 



possibly softens, melts and flows easily at 1300 ia iridescent streams 



sliowiiig surface-tension effects. The fusion shows incipient crystalliza- 

 tion. 

 Samarshiie (Arendal, Norway) : — powder, which is bright on the hot ribbon, 



softens possibly at about 1330, and flows at 1360. 

 Hielmite (Kerarfvet, Sweden): — signs of rounding in smallest particles at 



about 1340, melts and flows freely at 1435. 

 Aesehynite (Hitteroe, Norway) : — reddens litmus paper, and yields a white 



sublimate, softens visibly at about 1270 with signs of sublimation, melts 



to a slag, and flows with difficulty at 1415, more easily at higher 



temperatures. 

 Aesehynite (Saetersdalen, Norway) : — powder turns dark yellow on heating, 



and reddens litmus paper. Possibly fuses at 1305, and flows with 



difficulty at 1500. The glass shows the above-mentioned colour-clianges. 

 Aesehynite (Ilmengebirge, Ural): — softens at 1245, and flows freely at 1420. 

 Polyniignite (Fredericks vara, Norway) : — turns yellow, reddens blue litmus, 



and yields a white sublimate. Probably softens below 1400, but does 



not flow below 1550. The fusion segregates into globules. 



