Hi D thanks for writing in. OK. Let's examine the facts:
1. Gold Ring marked GALT 18k dug up on civil war site.
2. Jeweler according to your research was founded in 1802 and closed doors 7-8 years ago around 2002.
3. The American Civil War began on April 12, 1861 and most people agree that Lee's surrender on April 9, 1865 was the end of the war.
Diamonds are forever and gold isn't far behind. The gold nugget from which your gold wedding ring was first fashioned had been in the earth for thousands and thousands of years before it was mined.
The civil war site where the gold ring with company trademark was dug is in keeping with dates of the civil war and the dates in which the jewelry company was still operating. So based on the above facts, YES, it would be an antique gold wedding ring.
Some people bury their jewelry for certain reasons or because the piece holds very special memories.
Remember, in the Titanic movie when the aged Rose, a passenger on the Titanic, threw the "Heart of the Ocean" Pendant over the bow of the ship near the place where the Titanic ship sank, where she lost her true love ? The stone was a blue diamond, (fictional) but it highlights the fact that not may people would throw away a blue diamond unless they had a pretty good reason.
King Edward VIII, who abdicated the British throne for the woman he loved wanted the jewelry of Wallace Simpson dismantled after her death so that no one could ever wear it after her.
The Duchess of Windsor however succeeded him and he was never to have his wish.