Quantcast
  Due to a new server, slow response may occur for which we apologize Portal logo
Login/Register
Bactrian Gold Treasure from Afghanistan, coming soon....
/gemstones/king-gems-decorative-stones/page_351 - 2
 

Vitrum Annulare, Pastes

Vitrum Annulare, Pastes Page of 384 Vitrum Annulare, Pastes Text size:minus plus Restore normal size   Mail page  Print this page
344                 NATURAL HISTORY OF GEMS.
better pastes than those of the Regent could be produced in our times."
The new process rapidly diifused itself throughout Europe ; and when Goethe visited Rome in the last quarter of the century (1786-9), he found the making of such Pastes a favourite occupation with 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 ot 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 often sold to 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 vitreous surface of the upper 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.
* As an instance Clarac mentions having been shown a paste taten from a gem of Marchaut's, and actually retaining his usual signature, which had thus been metamorphosed into an antique Sard. With satis-&ctory vouchers of its having just been dug up at Otranto, it was sold at an enormous price to a .Neapolitan duJce, an enthusiastic but not expe­rienced amateur.
Vitrum Annulare, Pastes Page of 384 Vitrum Annulare, Pastes
Suggested Illustrations
Other Chapters you may find useful
Other Books on this topic
bullet Tag
This Page