Help with marks on Silver Plated Tray - CWS?

[love]

Can anyone identify the markings on and/or approximately date of this silver on copper tray? Thank you!

[dragonflywink]

Hi - your item was made by the Sheridan Silver Co., the crown/S/shield mark was used from 1946-74. Have seen the other crown mark at top before, but can't recall its significance other than it occasionally appeared on what would have usually been marketed as 'Sheffield Reproductions'...

http://www.925-1000/silverplate_S2.html

~Cheryl