This casting was done using the delft clay technique. My first attempt using a casting frame I have just made. Some very minor imperfections but nothing to detract from the piece.
I wouldn’t use it to remove a bottle cap, the cap would mark and may possibly bend the silver. Silver is just not as strong as iron. The silver version is about 25% heavier too due to the difference in specific gravity. Available from my shop here. I can’t change the lettering, but I could remove it to create a space for engraving.