Cartier Signed Art Deco Colombian Emerald Onyx & Diamond Platinum Ring

A rare vintage original, Cartier signed. Art Deco ring, circa 1930, bearing the French HP hallmark, centering an exceptional 4.0-carat Colombian emerald of remarkable color saturation, transparency, and luster. All with insignificant enhancement. The pyramidal cabochon emerald is framed by calibré-cut onyx and accented with baguette-cut diamonds in a platinum mounting, exemplifying the geometric precision and chromatic sophistication of the Art Deco period.

AGL Certified. Made in France. Cartier signed and stamped.

Certification: AGL Document #1151473

Certification: AGL #1151473

The significance of this piece extends beyond its prestigious Cartier provenance to encompass exceptional gemological merit rarely encountered in the market. The emerald's vivid saturation and remarkable transparency are immediately evident, displaying the prized "Colombian green" with extraordinary depth and luminosity characteristic of stones from the legendary Muzo and Chivor mines. The AGL certification confirming Colombian origin with insignificant oil treatment—the most minimal enhancement category recognized by leading gemological laboratories—attests to the emerald's natural, natural quality. The visible jardin (natural inclusions) confirms authenticity while the stone's exceptional clarity at over four carats places it among the finest examples of its type. Colombian emeralds of this caliber, exhibiting such superior transparency, vivid saturation, and fine luster, represent a minute fraction of emerald production and have historically commanded premium valuations. The H*P hallmark confirms French manufacture during Cartier's most celebrated design period, when the maison's Paris workshop produced some of the twentieth century's most architecturally significant jewelry.

The geometric composition exemplifies Art Deco principles at their apex: the contrast between the emerald's organic luminosity and the stark modernism of precision-cut onyx creates the period's signature interplay of verdant brilliance against graphic black and white elements. The calibré-cut onyx squares, individually shaped and channel-set to form a flawless halo, demonstrate the painstaking craftsmanship that distinguished Cartier's Art Deco production—each onyx piece custom-cut to achieve seamless geometric precision around the emerald's curved form. The flanking baguette diamonds provide crystalline punctuation to the composition, their linear form reinforcing the architectural rigor of the design. 

Cartier’s true golden era was in its Paris workshop, and French-hallmarked pieces from the 1920–1930 Art Deco period represent the maison’s purest aesthetics and craftsmanship — which is why serious collectors consider ‘Cartier Paris’ the highest standard.