Morning journal and courier., 1888-02-22

ence in them of large numbers of spherica bubbles, rarely pear-shaped, semetimel containing stringy portions showing hoy the bubbles had moved. When examined individually they always seemed to be filled with gas or air and formed part of a cloud the rest having the wayiness of a fused mixture. In natural rubies the cavities are always angular or crystalline in outline and usually filled with some liquid, or ii they form part of a Heather" as 1t is called by the jewellers, they are often ar ranged with the lines of growth. Hence the difference in appearance between the cavities in the natural gem and those in the fused gem is very great and can readi- ly be detected by the pocket-lens.
 Another distinguishing characteristic is, in many genuine rubies there is a silky structure (called "silk" by the jewelers), which, if examined under the microscope, is found to be series of cuneiform or ac- lcular crystals, often iridescent and arranged parallel with the hexagonal layers of the crystal When in sufficient number these acicular and arrow shaped crystals produce the astoria or star effect, if the gem is cut en cabochon form with the center of the hexa- gonal prism on the top of the cabochon Mir Kunz failed to find them in the artificial stone or even any of the marking of the hexagonal crystal which often can be seen when gem is held in a good light and the light allowed to strike obliquely across the hexagonal prism. The hardness of these stones was found to be about the same as that of a true ruby, 8.8, or a trife less than 9, the only difference being that the artificial stones were trife more brittle.
 The specific gravity of these stones was found to be 393 and 3.95. The true ruby ranging from 3.93 to 4.01, it will be seen that the difference is very slight, and due doubt less to the presence of the included bubble in the artificial stones, which would slightly de- crease the density. The color of all the stones examined was good, but not one was so brilliant as very fine ruby. The cabo- chons were all duller than fine, true stones. though better than poor ones. They did not differ much in color, however, and were evil dently made by one exact process or one at time. Their dull appearance is evidently due to the bubbles.
 The French syndicate referred the matter to NJ. Friedel, of the School of Mines, Paris, supplying him with samples of the stones for examination. He reported the presence of the round and pear-shaped bubbles and determined the hardness and specific gravity to be about the same as of the true ruby. On analysis he found them to consist of alumina with trace of chromium for the coloring mat ter. He states that he himself has obtained small red globules with these inclusions by fusing alumina by oxyhydregen light; and, although having no positive evidence, he be- Ieves these stones to be artifcial1y obtained by fusion. On receipt of M. Frieders report the syndicate decided that all cabochon or cut stones of this kind shall be sold as artificial, and not as precious gems. All sales effected thus far, amounting to some six or eight hun dred thousand francs, shall be cancelled and the money and stones returned to their respec- tive owners The action taken by the syndi- cate has fully settled the position which this production will take among the gem dealers. MT. Kunz says, and there is little reason to fear, that the ruby will ever lose the place it has occupied for so many centuries