DOI Page / Citation link:
https://doi.org/10.11588/diglit.5009#0342
316 HANDBOOK OF AMC1I2UOLOGY.
Garnets seem to have been little employed by the Greeks for
engraving upon, but were largely in favour with tho Romans of the
Empire. Some excellent intagli occur in the Almandine garnet, but
no certain Greek or early Grosco-Roman work is recorded on the
blood-red garnet. Tine Roman intagli frequently, and sometimes
imperial portraits, are to be met with on the guamaecino.
Ckystallus—Rock Crystal.
Rock Crystal (pure silica) was never used for intagli by the
Greeks, or in the Roman period. It was exclusively employed for
vases and cups. Intagli on finger rings of a solid piece of crystal,
are of the time of the Lower Empire. In Italy, during the Renais-
sance period, some important intagli on crystal have been executed.
Valerio Vicentino was famous for this style of work. In tho Cinque
Cento collection in the museum at Naples, is a magnificent casket of
silver gilt, with engraved plaques of crystal, representing mytho-
logical subjects, and various events in tho history of Alexander the
Great, in complimentary allusion to the achievements of Alessandro
Farneso, to whom it belong'ed. It bears the name of Joannes do
Bernardi. A casket of rock crystal, on which are engraved the
events of the Passion, by Valerio Vicentino, is in the cabinet of
gems in the Florentine Gallery. It was a present from Pope
Clement VII. to Francis I., on the marriage of his niece Catherine
do Medici.
Crystal has been often used both in ancient and modem times for
the purposes of fraud. In Pliny's time the art was well known how
to stain crystal so as to pass for emerald or any other transparent
precious stone. At the present day by placing a piece of coloured
glass under crystal cut to the proper form, it is made to pass for a
real gem, so as to deceive tho best judges. This kind of stono
has been termed " doublet " by jewellers.
Semi-Transparent.
Oi'alus—Opal.
l'liny thus describes the opal: " Of all precious stones it is the
opal that presents the greatest difficulties of description, it displaying
at once tho piercing fire of carbunculus, the purple brilliancy
01 amethyst, and the sea-green of smaragdus, tho whole blended
together, and refulgent with a brightness that is quite incredible.
Tins stone, in consequence of its extraordinary beauty, has been
Garnets seem to have been little employed by the Greeks for
engraving upon, but were largely in favour with tho Romans of the
Empire. Some excellent intagli occur in the Almandine garnet, but
no certain Greek or early Grosco-Roman work is recorded on the
blood-red garnet. Tine Roman intagli frequently, and sometimes
imperial portraits, are to be met with on the guamaecino.
Ckystallus—Rock Crystal.
Rock Crystal (pure silica) was never used for intagli by the
Greeks, or in the Roman period. It was exclusively employed for
vases and cups. Intagli on finger rings of a solid piece of crystal,
are of the time of the Lower Empire. In Italy, during the Renais-
sance period, some important intagli on crystal have been executed.
Valerio Vicentino was famous for this style of work. In tho Cinque
Cento collection in the museum at Naples, is a magnificent casket of
silver gilt, with engraved plaques of crystal, representing mytho-
logical subjects, and various events in tho history of Alexander the
Great, in complimentary allusion to the achievements of Alessandro
Farneso, to whom it belong'ed. It bears the name of Joannes do
Bernardi. A casket of rock crystal, on which are engraved the
events of the Passion, by Valerio Vicentino, is in the cabinet of
gems in the Florentine Gallery. It was a present from Pope
Clement VII. to Francis I., on the marriage of his niece Catherine
do Medici.
Crystal has been often used both in ancient and modem times for
the purposes of fraud. In Pliny's time the art was well known how
to stain crystal so as to pass for emerald or any other transparent
precious stone. At the present day by placing a piece of coloured
glass under crystal cut to the proper form, it is made to pass for a
real gem, so as to deceive tho best judges. This kind of stono
has been termed " doublet " by jewellers.
Semi-Transparent.
Oi'alus—Opal.
l'liny thus describes the opal: " Of all precious stones it is the
opal that presents the greatest difficulties of description, it displaying
at once tho piercing fire of carbunculus, the purple brilliancy
01 amethyst, and the sea-green of smaragdus, tho whole blended
together, and refulgent with a brightness that is quite incredible.
Tins stone, in consequence of its extraordinary beauty, has been