Unknown Hallmark (possible Sheffield??)

[caralody]

Hi. I collect silver or silverplated teapots. I have one with a hallmark of a letter S in a diamond followed by a letter S in a shield, followed by a letter P in a square. ( At least thats what they look like to me.) Any info anyone could give me on it (i.e. maker, year) would be greatly appreciated. You can view the pics at:

http://www.parkyourpic.com/uploads/28a290639a.jpg" onclick="window.open(this.href);return false;

http://www.parkyourpic.com/uploads/11dd86507a.jpg" onclick="window.open(this.href);return false;

Thanks so much...