THE GENESIS OF THE DIAMOND. 205 



the silica-magma at the comparatively low temperature given above, 

 how could it possibly have retained its forms of crystallization aiid 

 perfect faces at the far higher temperature and pressure which must 

 have existed under the igneous theory ? 



It seems a pity that Herr Luzi did not state the exact weight of the 

 diamonds upon which he experimented, both before and after his 

 experiments. The burning or absorption of the diamond in its 

 matrix is a strong argument against the contention that the blue 

 ground was once a molten lava. If a diamond placed in a graphite 

 crucible containing melted blue ground, which is subjected to a tem- 

 perature of only 1,770° R., changes its shape, could diamonds be 

 found perfect in shape, without a flaw, and with clear transparent 

 faces, so smooth that they have the appearance of having been pol- 

 ished? 



3. Some years ago a diamond weighing 28.5 carats, found at Kim- 

 berley, attracted the attention of the valuator. Its external surface 

 was smooth and crystallized, showing no other mineral except the 

 diamond itself, but the interior was white and not transparent. 

 Noticing this peculiar appearance, the valuator broke the stone in 

 order to satisfy his curiosity and found that a small perfect octa- 

 hedral diamond was inclosed in the center of the larger stone. Nor 

 was this all. There w-ere flakes of a wdiite mineral, not diamond, 

 attached to the fragments of the broken diamond. In appearance 

 the flakes Avere white, translucent, and crystalline, and about as hard 

 as steel. AMien heated in a closed tube, moisture was given otf. It 

 fused readily on platinum wire to a white bead. A iew grains of 

 this Avhite mineral were collected, and by analysis it proved to be 

 apophyllite, a silicate of lime and potash with IG per cent of water. 



If a mineral which is fusible at the ordinary temperature obtained 

 wdth a blowpipe, and which contains IG per cent of water, was formed 

 at the same time that the diamond crystallized, it is certain that this 

 did not take place under an enormously high temperature. How, 

 then, one may ask, did the apophjdlite become a part of this diamond? 



Herr von Tschudi" describes a beautiful crystallized Brazilian 

 diamond in the center of which was a leaf of gold. He obtained the 

 information from Dr. Mills Franco, who claimed that there was no 

 doubt or deception as to the identification of the gold. 



Occurrences of this nature tend to veil in additional mystery the 

 genesis of the diamond. 



4. Professor T. G. Bonnej^ ^ obtained from the Newlands mines, 

 40 miles northwest of Kimberley, specimens of a coarsely crystal- 

 line rock studded with garnets, technically called holocrystalline 



a Ti-civels in South Aiaerica, by .7. ,7. von Tsclmdi. 



6 The Parent Itock of the Diamond in South Africa, by Prof. T. G. Bouncy. 



