Postby Neruda » Tue Mar 14, 2006 8:38 am
dwt is the abreviation for pennyweight - an old measurement of approx 1.555 grams. In the case of your spoons 7 dwts of silver were used to plate a certain number of pieces - probably a dozen. In theory the more silver used, the thicker the plating and the better the quality. A1 (originally a naval expression) was also widely used to imply top quality plating.
Your pieces are probably English late 19th century.