I have a beautiful large sterling silver teapot, 995 grams marked on bottom PT905 inside a kite shape. At first I was unsure of the composition mostly because of the weight, so I started with an acid scratch test and knew for sure it was at least silverplated but it just had the qualities and finish of solid silver. At first I didn't want to damage the item by doing an acid file test, in the case it was only silverplated and leave an acid mark. Well I took the plunge and did a deep file test on the base in a groove where hopefully it wouldn't be noticeable. I bought new acid and did the test and let the acid just sit in the groove and surrounding surface. While using a jewelry loupe I observed and there was absolutely no fizzing or green. Immediately after I used some mild silver polish and the small dull spot the acid left cleaned up to absolute perfection, as if I never did the test. I did the test twice just to be sure. I'm pretty confident at this point this is solid silver, at least 925. I'm at a loss as to who could be the maker and can't find ANY information on this mark. It is certainly a quality piece. There is also a single calligraphy G monogrammed on the front. Any help with the age, period, style maker, or origin would be greatly appreciated. I have a hunch it might be a central or south american piece.
Thanks so much,