Oct. r, 1886.] 



THE TROPICAL AGRICCLTURIST 



281 



INVESTING IN PEECIOUS STONES. 



ALL ABOUT THE FIVE PRIMARY STONES. 



CoUectDis of Stones are apt to have their nerves 

 agitated I-. rumours of new mines, or threats that 

 the markii \ill be dehiged from the looted treasury 

 of King Th .; uaw, or destroyed altogether by some 

 discovery of how to make one ruby worth lO.OOU fr. 

 out of ten worth 1 fr. each ; but I have never found 

 persons wlio may perhaps have from t'100,000 to 

 4'2(K »,()()() worth of the stock so threatened to he in 

 the least disturbed by these alarms. Even the aston- 

 ishing increase which has taken place of late years 

 in the supply of diamonds seems only to have in- 

 creased, in still greater proportion, the demand for 

 them. Good stones are as dear as ever they were, and 

 really first-class stones dearer. Nor is there the re- 

 motest chance that '"real," though "non-natural," 

 rubies will ever be produced by any process of fusion, 

 welding together, or otherwise. The products would 

 not be ruby, though, chemically, exactly the same 

 substance. Crystalline formation is of the essence 

 of the ruby, sapphire, emerald, and diamond ; and 

 though exceedingly minute diamonds — less than the 

 one-hundred-and-fiftieth part of a grain— appear to 

 have been produced by allowing the vapour of carbon 

 to cool under enormous pressure, it spem practically 

 certain that large crystals have been tlia product of 

 extinct telluric forces operating through enormous 

 spaces of time, the effects of which art will never be 

 able to copy. 



Crystalline constitution is the condition of the 

 dischroism or double colour, and the power of disper- 

 sion of light, which make all the difference between 

 the mystic and ever-varying beauty of a true stone 

 and a piece of white or coloured glass. The ruby 

 may be softened by heat, and small rubies may per- 

 haps be thus welded together, as they are said lately 

 to have been by some cunning persons at Geneva ; 

 but in this process the crystalline character of even 

 the welded bits would be destroyed, a/ud much less 

 would the whole have any such formation. Again, 

 the ruby seems to owe much of its extreme beauty 

 and variety of colour to a fact which has not been 

 sufficiently dwelt upon in this connection. The ruby 

 and the sapphire are chemically the same substance, 

 or very nearly the same. Alternate layers of sapp- 

 hire and ruby are even sometimes found in the same 

 stone; and erroneous cutting has been known to 

 danuige immensely an inestimable ruby by "bring- 

 ing out the sapphire" — that is, by bringing out a 

 third and distinctly blue tint in the "table" over 

 and above the twin colours of the pure ruby. Now 

 it Iseems to me that some unequal mixture of the 

 colour of the sapphire in the body of a fine ruby 

 may account for one of the most inimitable beauties 

 of very fine rubies — namely, an exceedingly slight 

 and changeful inequality, or sort of smeariness in the 

 deep carmine of the lower facets, as seen through 

 the "table" and upper surfaces of the stone; a 

 quality which gives to its colour the same kind of 

 mystery and animation as is given to a space of 

 blue sky by the ever-present but all but invisible 

 and ever-changing shreds of white mist, with which 

 the clearest sky is always covered and without which 

 the blue would be as dead and hard, however bright, 

 as the splendid red of the imitation rubies now 

 manufactured in Paris : specimens of which may be 

 seen in a jeweller's shop where Piccadilly joins the 

 llegent's-circus. This effect must for ever remain 

 beyond the power of art to copy ; as also must an- 

 other with which a great expert has told me that 

 he considers the colour of the ruby to be somehow 

 connected. 



Very beautiful pink-rose-coloured rubies of great 

 size, four to six carats or more, are sometimes ab- 

 solutely Hawless ; but no ruby of the true deep and 

 glowning carmine and of more than three carats in 

 weight has probably ever been seen without fiaws. 

 Even in very fine and valuable rubies such flaws 

 are perfectly visible at the first glance of the naked 

 rye: but the most perfect "specimen ruby" ever 

 known a^ fir as F have been able to ascertain, though 

 "perfect ' ill lli> sense that it is perfect to the 



unassisted vision, will reveal, under a strong m igni 

 fier, at least one or two such little points or planes 

 of irregular reflection in its substance as tliose 

 whicli quite fill the body of a Mue opal and c luse 

 its many-coloured iridescence. It is a niostcuriout 

 fact that similar "flaws" seen to be similarl .- 

 connected with splendid colour in the emerald 

 though not so invariably as with the ruby. Largo,, 

 light-coloured, and flawless emerald-i are so common 

 as to bo comparatively worthless; and " aquam, 

 arine," which is nothing but a very l:,^ht emerald- 

 is found in absolutely faultless mass weighing 

 pounds, or even hundreds of pounds. Fine sapphires, 

 like emeralds, have usually some flaw or " feather " 

 in them ; but, " like emeralds and unlike rubies, are 

 sometimes to all appearance absolutely perfect. 

 These characteristic fiaws of fine stones are imit 

 ated by fraudulent manufacturers, but in vain. The 

 cracks which they produce in their silicious or 

 aluminous glass are too gross to escape detection 

 as the work of artifice, and they do not affect the 

 colour. But, while these imitated flaws are quite 

 unlike those of real stones, the substance of the 

 imitation stone, produced by fusion of alumina and 

 other earths by great heat, has unavoidable flaws 

 of its own, which easily distinguish it. On the 

 whole, it may be safely assumed that the chances 

 of any imitation or " production " ever endangering 

 the value of natural stones is so small that it need 

 not be taken into account by investors in them. 



Pearls, though inferior in indestructibility to 

 any of the precious or semi-precious stones, 

 hive at all times, on account of their extreme 

 beauty ranked with rubies, sapphires, emeralds, and 

 diamonds in value. They are subject to various 

 kinds of injury, none of which affect the four prim- 

 ary gems, which are practically indestructible. They 

 are easily scratched, are subject to discoloration 

 by absorption of effluvia, and to actual and sudden 

 decomposition by the presence of acids, even in the 

 atmosphere. An instance came under my own ob- 

 servation in which some lustrous pearls were change :! 

 in the course of a few days, into things just like 

 the eyes of boiled cod-fish, by the accident of a 

 vinaigrette having been placed in the jewel-case with 

 them. NotwithstandiuK this serious drawback, their 

 beauty is so surpassing that a fine pearl of large 

 size exceeds in value every other gem except the 

 ruby. A short time ago I had the pleasure of being 

 shown at Messrs. Garrard's a necklace of forty 

 splierical pearls, not at all so large as to look 

 vulgar and ostentatious, the largest, being onlv 

 forty grains. The price was £14,000 ; and the other 

 day I saw two pearls, one of fifty-four and the other 

 of about ninety grains, which were respectively 

 valued at fl,()00 and t'1,000 : that is to say, at 

 about t'l 10 and £180 a carat of four grains. Black 

 and pink pearls are just now of even greater value ; 

 but this is rather on account of their singularity 

 than their beauty, which is incomparably inferior 

 to that of tlie pure white pearl, with its faint and 

 changeful " photosphere " of all hues, 



Tlie pearl is even less capable of being success- 

 fully imitated than the ruby or the emerald. In a 

 fine pearl, tliough there is not the slightest transparency 

 or translucence, you seem somehow to see substance 

 and not superficies. It is an organic surface, and 

 cannot be copied by art. So with the forms of 

 pearls, which, though often mathematically perfect, 

 have a vitality and character of growth from within 

 which, though easily felt by the practised eye, is 

 not so easy to account for. The parabolic and 

 hyperbolic curves of fine pendant and egg-shaped 

 pearls seem somehow to be incapable of being copied. 

 I have one of about the shape and size of the egg 

 of the golden-crested wren ; and the beauty of its 

 form is a feast of which my eye is never weary. 

 Science is quite as much at a loss to account for 

 the formation of these exquisite gems in tlie pearl 

 oyster as it is to account for the hues of the finest- 

 coloured stones. Mr. Church, in his scientific little 

 tract, says : " That there are small quantities of 

 magnesia, oxide of iron, and silica in rubies and 

 sapphires of all burs has boon a'crrtained ; but this 



