BORON (svmb. B, equiv. 11) is a non-metallic element present in borafic acid (q.v.) and borax (q.v.). It was discovered in 1808 by Gay Lussac and Thenard in France, and Davy in England. The process followed in procuring 13. till lately was to mix pure and dry boracic acid (BO,) with thin slices of the metal potassium (K), and heat them in a tubc,when three atoms of the potassium abstracted the oxygen, forming potash (h0). and set free the boron (B). On &ailing and washing the mixture with cold water. the potash dissolved out, and left the 13. as a dark, greenish-brown powder. when landed. burned with a green filmy. and was re-formed into bar:tele acid, by combining with the oxygen of the air. Recently; however, WOhler and Devine have obtained B. by heat ing in a crucible at a high temperature a mixture of pure dry boracic acid and the metal aluminium, when the latter takes the oxygen forming alumina and leaves the B. as minute crystals interspersed through the earth alumina. These crystals possess great interest from their similarity in properties to pure crystallized carbon, or the aiamoud, and they are now known among scientific chemists as B. diamonds. They are remarkably transparent, arc tinged yellow or red (though the rotors may be acci dental, and rival the ordinary diamond in their luster and refractive power. B. dia
monds not only scratch glass, but also the corundum and the sapphire; and a real diamond, with which a few B. diamonds were crushed, had its edges worn away. It is apparent, therefore, that the B. crystals possess in a high degree the characters of the ordinary diamond; and though they have as yet only been obtained in minute specks, yet it is not too much to expect that the size will be increased, and the artificial B. dia mond come into the market as an article of ornament, to rival the natural carbon diamond in its mysterious power of flashing back the rays of light. Indeed, so like are these two kinds of diamonds, that they can scarcely be distinguished by outward char acters or signs; and it has been gravely suggested that some of the diamonds which now adorn the brow, the neck, or the arm, may be natural B. diamonds. They are very indestructible. requiring a high temperature to destroy them; and, like the true diamond, heat ultimately forms them into a coke.