QUARTZ (CITRINE) 487 



Citi'ine is sometimes very pale or almost colourless. Among deeper coloured stones 

 may be seen A\ine-yellow, honey-yellow, and saft'ron-yellow specimens, while others have 

 quite a pronounced brown tinge. Stones of a deep brownish-yellow colour are very like 

 topaz (Plate XIII., Fig. 2a), and those of a fine golden-yellow are quite equal in beauty 

 to yellow topaz, and can scarcely be distinguished on mere inspection from the latter stone 

 except by an expert. 



This variety of quartz is, in fact, constantly passed off as topaz, with which stone it has 

 nothing in common save colour. It is probably not going too far to state that this stone is 

 never either bought or sold in the trade under its correct mineralogical name, but always 

 under the name of topaz, perhaps with a qualifying prefix such as occidental, Indian, 

 Bohemian, Spanish. Used in this sense then, " Indian topaz " signifies not the saffron- 

 yellow topaz from Ceylon, already mentioned, but saffron-yellow citrine. By " Spanish 

 topaz" is understood citrine of a deep brownish-yellow shade, while the term "golden 

 topaz "^ is sometimes applied to golden-yellow citrine. The tei-m " false topaz ■" is also used, 

 but is usually applied to yellow fluor-spar. 



It is not difficult to discriminate between citrine and true topaz, for topaz, with a 

 hardness of 8, will scratch citrine. Topaz, moreover, is much heavier than citrine and sinks 

 heavily in pure methylene iodide, in which citrine floats. Finally, while topaz is always 

 leather strongly dichroic, citrine is scarcely dichroic at all. 



Citrine is of course only cut as a gem-stone when perfectly clear and transparent, and 

 its value as such depends upon the degree of its transparency, and the richness and purity 

 of its colour. The finest specimens are at least as valuable as correspondingly fine amethysts ; 

 and medium material, like amethyst, is sold for a few shillings a pound. The step-cut and 

 the various modifications of the table-stone are the forms usually adopted for citrine, as also 

 for amethyst, topaz, and coloured stones in general. 



It was usual formerly to regard citrine as a rare mineral only to be found at a few 

 scattered localities. Goatfell, in the island of Arran, where it occurs attached to the walls 

 of crevices in granite, was one, Bourg d'Oisans, in Dauphine, here associated with rock-crystal, 

 was a second, while others were mentioned in Hungary and Croatia. It first reached the 

 European markets in quantity in the thirties of the nineteenth century, having been 

 discovered in Brazil and Uruguay, whence it was sent with amethyst to the lapidary works 

 of Oberstein on the Nahe. The mineral occurs most abundantly in Brazil in the States of 

 Minas Geraes and Goyaz, but a large amount of material is also yielded by Rio Grande do 

 Sul, the most southern of the Brazilian States. The principal locality in Uruguay is the 

 neighbourhood of Salto Grande on the Uruguay river. In both of these South American 

 countries citrine is found, together with amethyst and agate, in amygdaloidal cavities in 

 melaphyre. In the neighbourhood of Mursinka, in the Ural Mountains, it is met with in 

 the gem mines together with amethyst, but in much less abundance. A variety of quartz, 

 which when strongly heated assumes a fine yellow colour and which can then be sold as 

 topaz, occurs in Spain at Hinojosa, in the province of Cordova, on the northern slopes of the 

 Sierra Morena. Several hundredweights of this stone is mined annually, but the aver*age 

 quality is poor and it does not sell for more than four or five francs per kilogram. When 

 cut it is bought and sold under the name of " Spanish topaz," but is not very much in 

 favour. A few fine specimens of citrine suitable for cutting have been found in North 

 Carolina, but here, as elsewhere in North America, the mineral occurs in very insignificant 

 quantities. 



