The Cartier Jumbo Gondole ref97051 and the Piaget "Black Tie" Beta21 ref15101: #SameOrDifferent?

• the Cartier measures 38 * 35mm, while the Piaget goes well beyond that with 44 * 40mm, due to the uber-sized and uber-important 1st Swiss quartzmovement Beta21, that makes the "Black Tie"-watch move;
• overall the design is not exactly the same but similar enough to allow a comparison: two stepped case in the Cartier while the Piaget comes with three of such steps because of its sheer size; interestingly, the steps are of same size with 3mm each -- by the way, this 3mm-step is exactly what in 1972 became the Piaget Emperador (each link is shaped like such a 3mm-step) and in 1979 it became the Gadroons in the Piaget Polo (alternating 3mm- and 6mm-links);
• furthermore, we see a cushion-shape in both, which is special and characteristic enough to see even more similarities in the design, next to the dial with its black printed roman hour-numerals and the inner-railroad minute-track;
• the "rare" Cartier Jumbo Gondole Horizontale ref97051 was made in at least 373pcs in total as the serial of the shown whitegold example (373) proves -- probably it is not the last one (for sure it is not the last one, see #500 below) and so assuming a production of more than 380 is of low risk and even >400 would be not a big surprise (*see below); the Beta21 Piaget ref15101 on a strap was made in less than 60pcs and just 8 (eight) examples in whitegold (some of these eight probably with a different dial): this is known by the Piaget-archive; by the way, this translates to approx 15% of the overall production in whitegold, which is a very common ratio in the early 1970s: we see same in the Patek, Rolex and IWC Beta21; in the Rolex King Midas; in the Rolex DateJust; in the Cartier Tanks; in the Patek Ellipse; and now, I would be very surprised if we see a significant different ratio than 15% (ie. 10 - 20%) in the Cartier Jumbo Gondole (Verticale or Horizontale, no matter); that would translate to a whopping 50 - 100 Cartier Jumbo Gondole Horizontale ref97051 made in whitegold;
• the Piaget was made completely in-house besides the C.E.H.-developed Beta21-movement: case, dial and even the 18K-gold movementholder -- all done by the back-then trend-setting manufacturer from La-Cote-Aux-Fees: Piaget; while the Cartier uses an ebauche (A. Schild caliber AS 1760) and the case was made by Guillod Gunther SA (poincon de maitre: Hammer[121]) and the dial by...;
• the Cartier was introduced in 1972 (earliest estimate) or even 1973 (several other sources point to that year: Anthony Traina at Hodinkee: *klikk), while the Piaget Beta21 is around since April 1970 as the more common ref14101 but the shown ref15101 "Black Tie" appeared and was sold already in 1972;
• Cartier acquired a significant share in Piaget in the late 1980s and took it completely in 1990;

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*) With a quick search several whitegold examples come up. It seems like in the first 300 of this ref97051 were made mostly of yellowgold, with a ratio of 10% or even less in whitegold -- which is typical for the early 1970s -- and in the #300s and following (so made in the late 1970s and in the 1980s) it seems like much (!) more were made in whitegold. NB: most in the second half of the 300s-serialnumbers were sold by MonacoLegendAuctions but there is also a serialnumber 500 (in... whitegold, of course), which was sold by Phillips Auctions in 2016: *klikk.