(Sigh)
Doesn't anybody reading this thread own a copy of the button picture-book by Alphaeus H. Albert titled "Record Of American Uniform And Historical Buttons"?
Your specific version of GA Seal button (which by the way is a "flat" 2-piece brass button) is shown in the Albert button-book as GA-17B. The only known specimens of it which have a name in the backmark say "Pettibone Bros. Mfg. Co." The company was in business under that name from about 1880 until it closed in 1975. However, Pettibone did not manufacture any buttons... they were made by the Waterbury Button Company. Your 2-piece (not 3-piece) GA Seal button is not shown in the Waterbury Button Co.'s illustrated catalog from 1900. So, it must have been made sometime later in the 20th Century.
You can view every page of that catalog in the .pdf file here:
https://archive.org/details/militaryallmetal00wate/page/10
Waterbury's 3-piece ("Staff") version of your button is shown on page 10 of the 1900 catalog.
There was no civil war era (or earlier) "FLAT" TWO-PIECE Georgia State Seal button which had a "lined background" and TWO curls of the ribbon on the columns. (That is why it is not shown among all the Georgia Seal civil war buttons at the Treasure Depot Button Project website.)
More evidence that your button is from the 20th Century:
Your button's backmark, saying "Superior Quality", is written in what is called plain block lettering. Very few button backmarks used plain block lettering until the 1890s... and that lettering-style became the "used-everywhere" standard lettering as the calendar clicked over into the 1900s.
Lastly... your exact same "flat 2-piece" GA State Seal button (except for the backmark) is still being made and sold by the Waterbury Button Company today. You can order one from the following page of the WBC's online catalog, here:
https://waterburybutton.com/product-detail/georgia-state-seal-30