58 
GEOLOGY OF THE SECOND DISTRICT. 
The minerals which are the most difficult to fuse, are the ones which exhibit this softened 
aspect; while the feldspar, sphene, scapolite, pyroxene and tourmaline present forms tolerably 
pei-fect. Zircon, which is quite common, and is the most perfect, seems to be an exception to 
this statement; its edges are always finely formed, sharp, and perfect. 
Another fact quite common, and equally interesting with the preceding, is found in the 
fractures and flexures of tlie crystals. They are finely seen in the long prismatic crystals of 
zircon and phosphate of lime. The annexed figure is a representation of a bent crystal of 
phosphate of lime. 
17 . 
That this substance should be capable of bending, requires a support on all sides, or else 
that the force should be applied while in a softened state! The surface exposed in the fissures 
look as if they were torn from each other; which favors the state I have supposed the crys¬ 
tal might have been in at the time'bf its injury. But it is quite common to see the crystals 
of lime fractured directly, and one portion rernoved beyond the axis of the other. In fact, 
very few of the larger crystals of the locality at Rossie, but have been broken, many of which 
are mended by a thin layer of carbonate of lime. The imperfections of the larger crystals 
are to be attributed to the fracture they have suffered, and to the numerous imperfections in 
the interior which I have already noticed. 
Most of the large crystals of zircon are either broken or bent. Figure 18 is an example of 
this kind. 
18 . 
Of the fact of a fracture," there can be no doubt, when we examine the ends or the surfaces 
of the broken fragments ; for we shall find them to fit or match with precision, and might be 
