BERYL (EMERALD): OCCURRENCE IN THE URALS 315 



witli basal plane (Figs. 62 a, and 63). They rarely exceed the size of a man's thumb, and are 

 usually smaller. Frequently they are broken across in one or more places, the cracks being 

 filled up with thin layers of caicite, so that as long as the crystal remains in its matrix it 

 appears whole and unbroken, the fracture only becoming evident when the crystal is detached 

 from the matrix. Together with the well-formed crystals are found rounded fragments of 

 emerald, a fact which affords a certain support to the theory that the caicite veins are not 

 the primary situation of the emeralds, but that they have been washed into these veins from 

 gneissic or granitic rocks. 



Some crystals have the peculiarity of falling to pieces, with no apparent cause, after 

 being taken from the mine. It has been sought to avoid this by placing the emeralds when 

 first uneai-thed in a closed box, thus protecting them for a few days from the action of light 

 and allowing them to dry slowly. This device is not, however, as a rule, successful. 

 Moreover, most of the emeralds which come from the mine clear, transparent, and free from 

 fissures, in course of time lose their transparency and assume the usual turbidity of this stone 

 owing to the development of fissures within them. In this connection we may recall the 

 statement that emeralds, both from this and from other localities, only acquire their own 

 particular hardness after they have been taken from the mine for some time. Fine emeralds 

 suitable for use as gems are known in Colombia as " canutillos," and poorer stones as 

 " morallion." 



Since there is nothing to indicate in what part of the mine emeralds are likely to occur, 

 the workers simply loosen blocks of rock from any part of the walls until a nest of emeralds, 

 the presence of which is indicated by green quartz crystals, is met with. This is then 

 carefully broken out and taken away. The material loosened from the walls of the mine is 

 allowed to fall to the bottom, and when it has accumulated to a certaint extent it is washed 

 out into a canal consti'ucted for this purpose, by the sudden fall of a head of water stored 

 on the heights above the mine. The canal empties itself into the Minero, which carries the 

 mine debris still further away. This is the method adopted at the present day, but in 

 former times when the Spaniards were in possession the workings wei'e all underground. 



The only other locality of importance for emeralds beside Colombia is the Ural 

 Mountains. There is here only one mine from which emeralds are obtained, the same in 

 which Uralian chrysoberyl, that is to say, alexandrite, is found. It is situated on the right bank 

 of the Takovaya, a tributary stream of the Bolshoi Reft (that is to say. Great Reft) which 

 flows into the Pyshma, eighty-five versts (about fifty-seven miles) east of Ekaterinburg. 



The finest of the Uralian emeralds are quite equal in transparency and beauty of colour 

 to South American stones. In this, as in other localities, perfect crystals are rare, the 

 majority being fissured and opaque, and the colour, in many cases, being irregularly 

 distributed or too pale. The crystals commonly have the form of a hexagonal prism, often 

 terminated irregularly, but sometimes with a basal plane like Colombian crystals ; other 

 forms scarcely ever occur. In size Uralian emeralds often exceed those from other localities, 

 especially South America. Some of exceptional size have already been mentioned ; the 

 largest have a length of 40 centimetres (15| inches), and a thickness of 25 centimetres, but 

 they are not, as a rule, of good quality. 



The mode of occurrence of the emerald in the Urals is similar to that in Egypt, but 

 differs from that in Colombia. The stones are found embedded in a tnica-schist, which is 

 interfoliated with chlorite-schist ; this is also the mode of occurrence at Habachthal in the 

 Salzburg Alps. A crystal of emerald in a matrix of mica-schist from the latter locality is 

 represented in Plate XII., Fig. 2. Scales of mica are found on the sm-face of, or inclosed in, 

 emerald crystals from all these localities. Uralian crystals occur singly or in groups ; they 



