Nope: Gen. Patton's S&W .357 Magmum (Registered Model) was blued.
The order was placed by Lt. Col. Patton on September 9. 1935. He specified the following features:
Barrel Length: 3 1/2 inches
Front Sight: McGivern (gold bead)
Rear Sight: Large "U"
Revolver to be sighted in @ 15 yards using S&W 357 Magnum ammunition; Dead center hold.
Include: Wesson Grip Adapter (attached).
Cost: $48.00
Admittedly, a Registered Magnum cost a lot more than $718 these days, but that's because it's the better part of a century old. But $718 will certainly buy you a pretty solid revolver or semi-auto.
Patton's side arms were a Colt Single Action Army, and a registered Smith & Wesson .357 both in nickle. No model 10 or predecessor....