Visual Description
The Quadrant is a square Tank Obus whose Roman numerals sit on the bezel rather than the dial. A wide bezel carries the hours in blue enamel, with an inner enamel minute track, around a plain matte white dial signed only Cartier at the top and Paris at the bottom. Monaco Legend describes the enamel as champlevé and the hands as blued steel épée.
The case is 18k gold with the bullet-shaped lugs of the Obus, a beaded crown set with a cabochon sapphire and a back held by four screws in the band. It comes in two sizes, about 25 mm and 19 mm square, on a leather strap with an 18k gold Cartier deployant buckle or on a gold bracelet. Christie's catalogs the large size at 25 mm square.
Reference Significance
The Quadrant moves the numerals of the Tank Obus from the dial to the bezel. Where the quartz Ref. 1630 has painted black Roman numerals, a railroad minute track and the hidden signature at VII on a silvered dial, the Quadrant leaves the dial bare except for Cartier and Paris and sets the hours in enamel around it.
No catalog gives it a reference number of its own. Christie's lists it by name as the Quadrant, and the numbers on its case backs, which begin A100 or A101, are case numbers shared across both sizes rather than a reference.
Historical Context
The Quadrant belongs to the 1980s. Fortuna writes that Cartier introduced it among many new models of the decade, and auction houses date examples to the 1980s, one to circa 1985.
Christie's has cataloged the earliest dated example of the design, a 25 mm watch of about 1980 with a hand-wound Cal. 21, without the Quadrant name, and notes that the design is illustrated in Le Temps de Cartier by Barracca, Negretti and Nencini. Every example cataloged under the Quadrant name in the records we opened is quartz.
Cartier came back to the idea later. A Tank Obus of about 1996, cataloged as the Rectangulaire à Pattes Vis Armurier, also has Roman numerals on an enamel bezel, but in black, on a case of about 23 × 24 mm with a guilloché dial and a hand-wound movement. It is a different watch from the Quadrant.
What to Look For
Start with the enamel. The numerals and minute track on the bezel should be complete, even in color and free of chips, cracks or retouching. Then check the bullet lugs under magnification for dents, asymmetry and polishing, as on any Obus.
Turn the watch over. The back should be held by four screws in the band, and the case should carry a number beginning A100 or A101; Monaco Legend and Fortuna record A100721 and A101494 on yellow gold examples. The dial should carry only the Cartier and Paris signatures, with no numerals, and the hands should be blued steel épée. A quartz movement is expected, apart from the rare early hand-wound example.
Original Cartier gold bracelets, deployant buckles, boxes and warranty papers have survived with several examples. They help confirm the size, metal and date of an example and make it more desirable.
