Can anyone help with identifying this mark?

[bbrouhard]

Requesting some help with identifying this mark and an approximate date of manufacture.
Is it Silver Plate or Sterling?

Thanks!

[Traintime]

Check here to start under silverplaters unidentified (suspected to be Continental Sheffield): https://www.925-1000.com/silverplate__Unk.html

[Traintime]

Next follow this sample and the links to further discussion by Trev: viewtopic.php?f=18&t=55773&p=178780&hilit=continental+sheffield&sid=33c2b31167c8ab84be0dadf2ced10ac9#p178780

[bbrouhard]

Thank you both so much! I couldn't make out what the shield design was. Your help is very much appreciated.