1 32 Mineralogical Journey. 



derives its chief interest in the eye of the mineralogist. Of all these, the 

 Garnet is the most conspicuous ; vast heaps of which are accumulated 

 about the two most southerly excavations, and which continues daily to 

 be raised in great quantities, especially in the working of the shaft above 

 alluded to. It is of a red color, and for the greatest part, massive ; 

 occasionally, however, becoming granular, and where grains of quartz 

 or calcareous spar are intermingled, shewing faces of crystallization. 

 When the quartz is in layers of considerable size, the Garnet some- 

 times crystallizes into it, in the most beautiful manner conceivable ; so 

 that on lifting off the layer of quartz from a mass of the garnet, we 

 have a surface invested by crystals, the richest in point of color, lus- 

 tre and finish, in which this species ever occurs. It is very rare, 

 however, to find surfaces of considerable dimensions thus coated : 

 those half an inch, or an inch over are pretty frequent. The indi- 

 vidual crystals rarely exceed one eighth of an inch in diameter. 

 Their color is that of a very dark and exceedingly rich blood-red, 

 sometimes becoming nearly black. The most perfect of them 

 have their faces wholly free from striae. The form of the crystal is, 

 universally, that of the triemargine of Haiiy. In consequence, hov/- 

 ever, of the undue extension of the tangent plane (a), the bevelling 

 planes (c) together with the primary faces (P), are so reduced as of- 

 ten to be scarcely perceptible ; thus imparting to the crystals the gen- 

 eral figure of the trapezohedron. 



Where calcareous spar occurs in this mixture of magnetic iron 

 ore and garnets, superb crystallizations of Epidote, of a fine pistachio 

 green color, are often found ; many of the crystals being regu- 

 larly terminated at both extremities, and extremely complicated and 

 various in their modifications. Among them, however, neither of 

 the two preceding varieties of form ever occur. The smallest crys- 

 tals possess a high degree of transparency, and present the curious 



