Bobby5 sent me a Private Message asking me to comment about his brass 1-piece "flatbutton." He (and others here) may already know some of the following info... I'm posting it for anybody who doesn't already know.
"Rolled-brass" (not solid-cast brass, nor thin machine-stamped sheetbrass) 1-piece flatbuttons with a blank front date from about 1770 to about 1850, depending on the form of shank/loop on its back and how it was attached. Bobby5's flatbutton started life with a plain front, and at some point in time a Jeweler did some fine hand-engraving work on it, inscribing a "lined" Old English letter C. I should mention... although many diggers call it a "script" letter, it isn't that kind. See the terminology in the button-book by Alphaeus H. Albert.
There are two possibilities about the intended purpose of the engraved letter C:
Possibility #1- We know with certainty that wealthy persons purchased "Family-name Initial" buttons (as a version of Livery button) during the time-period of Bobby5's button. Use of an Old-English letter was popular with the public in that time-period. See the photos of a 2-piece example, below. The Ebay seller of that button insisted it was a Confederate Cavalry letter-button... but its maker, the Scovill Manufacturing Company of Waterbury CT never made any Confederate letter-buttons.
Possibility #2- Because Bobby5 found the button in Texas, where the Confederates had great difficulty in getting hold of imported British-made CS Military letter-buttons. So, it is at least "theoretically possible" that a wealthy Confederate cavalry officer paid a jeweler to engrave some flatbuttons with the Old-English letter C, to imitate the unavailable CS Military-issue 2-piece brass ones. Although there is no ON-PAPER historical-document evidence of that being done to flatbuttons, and no such 1-piece brass flatbutton is shown in any of the books on civil war buttons... I've personally owned two flatbuttons which were hand-engraved "II VA" (2nd VA Regiment). Both of them were dug at Petersburg VA where the Confederate 2nd VA served during the siege of that city in 1864-65.
Summary:
Unless Bobby5 found his hand-engraved Old-English C flatbutton at a site where Confederate Cavalry relics have been dug, the button is 99% more likely to be a civilian "Family Initial" button.