The crest that is being sold as the family crest with the blacksmith tools is probably a guild crest. Henry Catron discovered the crest on a mug in a museum in Germany. He added the chain symbolizing the chain developed by Fritz Kettenring in 1401 and was granted a half house for his invention. The chain would not kink. There is an original crest from the twelvth century from Switzerland that depicts a key with a knights helmet above it and has Kettenring on it. Email me and I will tell you how to obtain a copy of the crest.