Fine Revivalist Necklace with three intaglio gems, three colors enamel, urns

ARCHAEOLOGICAL REVIVAL NECKLACE, 19th century, 18k gold. enameled in three jewel-like colors, intaglio engraved gems, urns and anthemia rosettes.
Band of woven gold, 1/4” wide, terminates in two square ornamental plaques and fastens with a rectangular box lock, applied with twisted wire, enameled in three jewel-like colors.

In front, the band centers between matching square plaques, three medallions, each centering a translucent intaglio carved gem above three urns. A paneled shell of red enamel and gold crowns each gem; below each, a gold, blue and white zig-zag patterned collar.

Each of the three gems, respectively reddish, green, and pale purple, is intaglio carved with a different classical figure.
Each engraved gem is oval, 14.5 x 12 mm; bi-convex, 4.1 mm deep.
The three framed intaglios are separated by double row of foxtail chain, strung with tubular and round gold beads, the two tiers connected by blue enameled rosette/anthemia flower-heads.
The box ornaments, lock, medallion frames and urns are decorated in blue and white enamel, granulation and applied twisted gold wire-work.
Overall Length : 16”
Gross Weight : 1.5135 oz troy.
Metal & marks : tested 18k; no identifying marks found
Provenance : direct descent through a Baltimore family
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