MAKING JEWELS FROM DUST.

Oamaru Mail, Volume XXXIX, Issue 10760, 6 May 1911, Page 2 (Supplement)

MAKING JEWELS FROM DUST.

There was to be seen in a great London' jeweller's recently a distinctly modern magician with ease, precision, arid .despatch. The apparatus which makes such an amazing thing possible is in reality simplicity' itself." It is one of those machines which makes one "wonder why nb one thought of it before." There is what is technically termed a chalumeau, which is a. species of small crucible made of fire-proof stone. This is heated by a fierce gas flame raised to a terrific temperature by oxygen. ;In the centre of the crucible is a little pedestal, above which is a long narrow tube, which feeds the furnace with the matter for the manufacture of the. jewels. In the case of rubies this matter consists of real rubies which have been pulverised to powdery dust. This dust is placed in a minute sieve of the finest possible mesh. Every three seconds a little electrically driven hammer strikes the sieve a tiny tap, and a- few grains, of. the pulverised ruby powder fall through the tube.on a red-hot disc Tielow. Gradually, solidifying the instant they have fallen, the particles of ruby dust are piled up into a solid, which, constitutes the manufactured ruby in the-rough. The smaller of these rubies take about a quarter of an hour to make, and tho time occupied in their manufacture increases in pro|>ortion to their size. Some idea of how these rubies can he manufactured by the thousand may he understood when it is mentioned that one operator ran watch and manipulate the whole row of the.-.- crucibles. As soon as the ruby ha* hi-en removed from the crucible mi'! hn.s cooled it is ready j for rutting, and so perfect are the 1 stones that it is impossible even fur an expert to (!■-■••••■; rh" d-tien-nn _b"twe>-u them and the real .-t"t:e.» with the naked eye. A very power: ill magnifying til.iss b- t , to be f'Ti!|•'• -yr 1 ! to discover the ditT'-puee.

Sapphires arc in i rfisame way. except that. i>i ruhy dust, alumina i.« otic the principal ingredients. *M:e pr<>ce>> i'T emorahU is different, but in the case of ::l! three stnnes it may lie said that. m> ah.-.ilutely like the real stones are they, in Paris j the pawnbrokers are already refusing to j take any colored stones in pledge.