I am not a Colt guy, but that looks like a Colt New Service made for the US army as the model 1917, to go along with the S&W 1917. Both made to fill a need that wasn't able to be covered by the 1911 production numbers. It should be chambered for the 45 ACP.
He said it's the Model of 1909, which is chambered for .45 Colt, not ACP. The model should be marked on the butt, by the serial number. I suspect he saw that and that's why he posted that it's the M-1909. But the pics don't enlarge and I can't read the markings.
This gun is also a military variant of the New Service, made for use in the Phillipines, to stop Moros until the M-1911 could be refined and adopted. It was intended to do better than the weak .38 Long Colt could. That was weaker than the .38 Special.
Larger photos are needed.
I don't understand the frequent attitude here that one should only know about S&W's. Gun enthusiasts should know at least the basics about most famous brands and their major models.
We should certainly know the official US-issued handguns since before the Civil War.
BTW, the M-1909 was originally blued, not Parkerized. The M-1917 did have a dull gray finish, or did on all that I've seen. But many were refinished for issue in WW II. S&W M-1917's were blued.
Also, the barrel of the Colt M-1917 is tapered. The older M-1909 was not, and the extracror head had three lobes. These changes were mirrored in Colt's commercial production of the New Service. By 1928, they also rounded the cylinder release latch.
The Colt lady may not be well trained, but I'd like to see that serial number in larger scale. Larger pics overall would certainly estblish what you have.
We also need pics of the Officer's Model Match revolvers to comment on them. If you have the production dates right, the fixed sight version was then the Army Special, renamed Official Police about 1926.
And we'd love to see the M-1911A-1, in The Lounge section of the board, probably. Members can tell you a lot about it there, beyond what should be obvious. Some members are very knowedgable about the .45 autos.