344 SYSTEMATIC DESCRIPTION OF PRECIOUS STONES 



exceptional. The dimensions of two exceptionally large stones have been given as 5| and 

 6 lines in length and 4| and 7 lines respectively in thickness. Other colour varieties of 

 precious zircon, which accompany hyacinth in Ceylon, occur in crystals of larger size, fine 

 stones a centimetre in length being by no means unusual. There is no doubt that the 

 difFerent varieties of zircon found in the gem-gravels of Ceylon have been derived from the 

 same rocks in which the sapphires, for example, with which they are associated, also took 

 their origin. In a few rare cases crystals of hyacinth have been found actually in the matrix, 

 which is a granite or gneissic rock, like the mother-rock of sapphire already described. 



Compared with Ceylon, other localities for zircon are unimportant. Many supposed 

 occurrences in India are by no means well authenticated ; such as, for example, in the 

 alluvial gravel at Ellore in the Madras Presidency, and in granite at Kedarnath on the 

 Upper Ganges. The occurrence of hyacinth with ruby in Upper Burma has been 

 reported. 



The occurrence of zircon in Europe is well established, but unimportant. It is found 

 with sapphire in sands, very similar to those of Ceylon, in the Iserwiese in the north of 

 Bohemia ; the crystals from this place are, however, smaller in size and fewer in number 

 Ihan in the sands in Ceylon. These zircons, sapphires, and other precious stones with which 

 they are found have been derived from gneiss. The hyacinths which occur in the streams 

 near Expailly, in France, have been weathered out of basalt ; here again the mineral occurs 

 under the same conditions as in Ceylon, but in small crystals few in number. 



The occurrence of zircon in Australia, though of little importance in the trade, must 

 not be forgotten. It is found in auriferous, and also in diamantiferous, sands, more 

 especially at various places in New South Wales ; fine specimens have been met with at 

 Mudgee in this State. 



Fine, richly coloured zircons are found in the gold-sands of North Carolina in the 

 United States ; the crystals are unfortunately, however, too small for cutting. 



In conclusion we must consider the manner in which zircons are used in jewellery. 

 The coloured stones are most frequently cut as table-stones or thick-stones, or sometimes 

 they are given step-cut or brilliant-cut forms, according to their transparency and depth of 

 colour. Fine stones of a pure colour require no special devices to improve their appearance, 

 but inferior specimens are mounted on a gold foil or in a closed setting lined with black. 

 Colourless stones, especially those which have been burnt, are usually cut as rosettes, a form 

 which, on account of the brilliant lustre and absence of any play of prismatic colours, is 

 more suitable than the brilliant, though the latter is sometimes employed. These burnt 

 hyacinths were at one time, on account of their peculiar dusky lustre, used in mourning 

 jewellery in preference to diamonds. 



Hyacinth is not worth much at the present time; the demand for the gem has fallen 

 off very considerably, and the genuine stone is rarely met with in the trade. Quite small 

 stones are, of course, cheap, on account of the supply being large ; it is only larger stones 

 that are of any appreciable value. A good, faceted 1 carat stone of fine colour is valued 

 at from 50s. to 75s., while a number of small stones of similar quality and weighing 1 carat 

 together would not fetch at the most more than 10s. or 12s. Corresponding values also 

 hold good for zircons of other colours. 



The similarity in general appearance between hessonite, or cinnamon-stone, and 

 hyacinth, and between diamond and burnt hyacinth, together with the methods by which they 

 may be distinguished, have been already mentioned. Another stone which may resemble 

 hyacinth, more or less, is yellowish-red corundum, known on this account as " oriental 

 hyacinth." Its lustre is as brilliant and strong as that of true hyacinth, from which it is 



