I’m trying to find out more about this bottle and its approximate value. I bought it at an antique shop in Amsterdam, Holland in 1976. It was found in a canal in Amsterdam. It has an embossed glass stamp with the words Constantia Wyn on the side. This winemaker is in what is now Republic of South Africa. I believe the bottle was probably made in Holland in mid to late 1700’s, then shipped empty to the Dutch colony in South Africa where it was filled with wine and shipped back to Amsterdam for consumption and tossed into the canal there. A bottle fragment with the same seal was found among the sunken remains of an English ship called Severn which sank off the coast of Delaware in 1774. I’ve attached 4 photos. Any more info would be much appreciated and would love to know what its estimated value is. Thank you.