I recently acquired a very large tray with hallmarks that appear to be a swan variant. The swan is on a triangle above another triangle with an unidentifiable mark. Both are superimpose upon a "tombstone". There are letters to either side. I've seen that the swan is used on small articles and on imports. However, what quality of silver does the swan represent?? ...and what is the era of the marks I have. URL to a somewhat poor picture is:
http://stainedglassartworks.com/bay05b/hallmark.jpg
Regards,
jim