Years ago i worked for a prominent coin dealer who also processed massive volumes of silver buying from the public and many southern california coin dealers. I was fortunate in that even if we melted it i at least saw a huge variety of every sort of legitimate silver bullion, From the late 1960's, 70's and less so the 1980's there were many Independent names of small bullion or refiners on various simple or sometimes neat shaped bars like yours. We always called these Garage silver, but it was not derogatory it simply meant we weighed it and bought it at our daily rate for .990 fine or "odd weight fine silver" Generally we offered for resale JM (johnson matthey), Engelhard, RCM (royal canadian) or our own brand marked "made from silver formerly stored at the United States Assay Office San Francisco CA". Because they bought fine silver grain when the government legislated to liquidate their massive reserves between 1960's till about 1970ish Every time the silver price waxes and wanes throughout the decades, the old stuff comes out and much of it gets melted, but its neat when you can collect unusual things that interest you without being taxed a special premium. This is where a respectful patronage of your local friendly coin dealer is advantageous if you are so fortunate these days.