71 



farther in small intermediate spaces in the albite are found, 

 filled with clear, bluish green fluorite, at first only a single 

 individual in each interval ; the albite borders on the fluorite 

 with small, clear crystals. Farther in the fluorite becomes more 

 and more predominant over the albite, and at the same time 

 these two minerals are joined by a very large number of small, 

 green crystals of garnet, so that the whole mass now consists of 

 an elementary matter of grained fluorite (size of the individuals 

 1 — 3 cm.), in which innumerable crystals of albite (1 — 3 mm.) 

 and garnet (c. 1 mm.) are swimming. No doubt, however, none 

 of the crystals of the two last-mentioned minerals are found 

 quite freely developed in the fluorite; but they form, as far as 

 can be seen, everywhere a quite loose, continuous texture, so 

 loose, that we are forced to suppose that the fluorite has 

 been formed about contemporaneously with the other minerals. 

 Nearer to the centre crystals of ilvaite are further added to the 

 mass; the belt in which they are found, has a breadth of about 

 1 dm. ; they do not reach the crystals of garnet and albite in 

 number. Neither have I succeeded in finding one single com- 

 pletely developed crystal of ilvaite; but 

 some crystals have, at all events, only 

 been connected with the earlier formed 

 crystals of garnet and albite by a quite 

 inconsiderable part of their surface. Inside 

 this belt all these three minerals disappear 

 at once, so that we have now a pure, 

 grained fluorite varying between bluish 

 green and violet. In the centre, finally, 

 appear a few rosettes of haematite, reach- 

 ing the comparatively considerable size of 

 3 cm.; they are partly found in cavities. Fig. n. Ilvaite, typeXV. 

 while such otherwise are not found throughout the mass. 



The crystals of ilvaite are rather insignificant; the size varies 

 from 1 — 4 mm., the form is about as in the annexed figure. 



