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Vitrum Annulare, Pastes

Vitrum Annulare, Pastes Page of 453 Vitrum Annulare, Pastes Text size:minus plus Restore normal size   Mail page  Print this page
358                              VITRUM ANNULARE.
Some of them indeed, particularly the Sardoine (brown Sard), have been imitated better subsequently, so far as the tone of the colour is concerned, but nevertheless, in spite of the modern improvements in the art of glass-making and enamels, and in spite of the advance of chemistry, it is very doubtful if better pastes than those of the Eegent could be produced in our times."
The new process rapidly diffused itself throughout Europe ; and when Goethe visited Rome in the last quarter of the century, he found the making of such pastes a favourite occupation of the dilettanti residing there. Even at the present day the Romans display extraordinary skill in the art : I have seen some of their pastes, especially of the opaque sort like the Sardonyx, that could only be distinguished from the true gem by the file. To baffle this mode of detection, the ingenious device is resorted to of backing the paste with a slice of a stone of the same colour. When set in a ring the junction is concealed, and the back with­standing the test of the file enables the composite to pass muster for a real gem, adorned with a precious engraving." The same method has been long, and still is, largely adopted for counter­feiting the coloured precious stones, the Ruby, the Sapphire, and the Emerald. A paste of the proper colour, backed by a piece of crystal facetted so as to impart the requisite brilliancy, is palmed off upon the unwary for a gem of the first class, nor is the fraud suspected until the wear of some months begins to tell upon the surface of the upper vitreous layer. Pliny mentions a similar trick as practised by the lapidaries of his day in the case of the Sardonyx, its three several strata being made up out of three different stones, each of the best colour for its position, and the whole cemented together with Venice turpentine/ still preferred for the purpose on account of its perfect transparency.
Wedgwood's seals and camei close the series of modern pastes :
Vitrum Annulare, Pastes Page of 453 Vitrum Annulare, Pastes
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