Actually "red9" Mausers are one of the most common and least valuable,(they have a red 9 on the handle and are 9mm). My understanding is that the terms of surrender,(Treaty of Versailles) only allowed them to produce guns in non-military(.30 Mauser) cals. The Chinese version in .45 is like a Luger in .45, very rare and very valuable.
Not quite.
Lot's of good info here,
http://www.1896mauser.com
* Prewar Commercial, of two minor variants - around 240,000 made between about 1905 and 1912-14
(In the C-96 context, the "war" is always the Great War of 1914-1918.)
* Wartime Commercial - around 144,000 made between 1912-14 and 1918
* 1916 Prussian Contract - a.k.a. Red 9 - around 135,000 made between 1916 and 1918
* Postwar Bolo, of two minor variants - around 345,000 made between the early 1920s and 1930
* M-30, of several minor variants - around 120,000 made between 1930 and 1937
* Schnellfeuer - close to 100,000 made between about 1932 and 1937 - rare in the USA, thanks to the 1934 National Firearms Act
Postwar Bolo
This was the first major variant out of the Mauser factory after the war. Production started in the early 1920s, perhaps 1922.
Due to the terms of the Treaty of Versailles, German pistols were limited to 100 mm barrels or shorter, and calibers under 9mm. Mauser satisfied these restrictions by reviving an older variant, popularly known as the Bolo. Although often called the "small-frame" Mauser, most of the frame is identical to that of the full-size guns. The grip is notably smaller, but all the internal parts are identical to those of the larger pistols. The original Bolo may have been an attempt to make the gun slightly less bulky overall, a notion supported by the fact that nearly all of the very early six-shot guns were Bolos - that is, they had the smaller Bolo grips and the short (100 mm, or 3.9 inch) Bolo barrels. See more on this subject here. However, the postwar Bolos all have 10 shot magazines.
The Postwar Bolo is identical to the Wartime Commercial, with these exceptions -
* 3.9" barrel with the front sight on a barrel band
* No proof stamp on locking block
* Small grip
* 22 groove walnut grip panels
* Barrel serial number and proof stamps change places - serial number is now on side of chamber, proof stamp is on diagonal flat above it
* Lanyard ring swivels from side to side, rather than fore & aft
The Bolo dominated postwar production throughout the 1920s. It retained the WAFFENFABRIK MAUSER markings, even though the factory name changed to MAUSER-WERKE A.G. in the early 1920s. System Mauser gives an observed serial range of 444476 to 793350 for Postwar Bolos. My own database lists Postwar Bolos from 440864 to 674447.
Around serial 500,000, a Mauser banner mark was added to the left side of the Bolo frame.