quattro[Moderator]
6108
Patek Philippe ref. 2526 & 3428
1) Ref. 2526, introduced in 1953, was Patek Philippe's first automatic wristwatch, powered by caliber 12-600 AT. Rolex launched its first automatic watch in 1931 with the Bubbleback model, but decided to protect its patent for 22 years. So Patek had to wait.
2) Production ended in 1959. Ref. 2526 was followed by ref. 3428, which was almost identical, except for a new caliber 27-460 with, among minor differences, a rotor decorated with côtes de Genève.
3) Ref. 2526 was produced in four metals: around 7.000 pieces were made, mostly in yellow and rose gold. Very few white gold (20) and platinum (25) examples are known to exist.
4) If you want to read more about these references:
Enjoy!
A/ REF. 2526 with caliber 12-600 AT
1/ ON STRAP
YELLOW GOLD
Enamel dial (credit: the keystone)

credit: d-timepieces

credit: @alfwatches
Gobbi Milano signed dial (credit: @garyg_1)

Black dial with mirrored arabic numerals (credit: hodinkee)
Tiffany signed dial with ”do unto others as you would have them do unto you" (credit: hodinkee)

Andy Warhol’s personal piece with Breguet numerals and needle hands (credit: hodinkee) - Last photo with leaf hands (credit: @jardin.watch2)
WHITE GOLD
Enamel dial (credit: hodinkee)

Diamond indexes (credit: on behalf & @bobmaron for the wrist shot)

credit: hodinkee
PLATINUM

credit: hodinkee

credit: @2tonevintageofficial
2/ WITH BRACELET (note the incredible variety of patterns!)
YELLOW GOLD
First ref. 2526 with enamel dial sold to J.B. Champion with a dedication letter from Werner Sinn in front of the “Henry Stern Agency”; the 27th of July 1953 (source: “Collezionare Orologi” by Osvaldo Patrizzi - credit: satnaruci)
Same J.B. Champion watch with a different bracelet as auctioned at Sotheby's Hong Kong Important Watches sale on April 7 2024 (credit: sotheby's)

credit: the keystone

credit: on behalf

credit: hodinkee
credit: Sjx
ROSE GOLD

credit: on behalf

credit: hodinkee

credit: satnaruci
WHITE GOLD

credit: hodinkee

credit: bonhams
PLATINUM

Tiffany & Co signed dial with bracelet (credit: @jonbinla & hodinkee)
Diamond indexes (credit: watchpro)
B/ REF. 3428 with caliber 27-460

Yellow gold (credit: on behalf)
Platinum (credit: on behalf)