Depending on the coin store, you will the spread closer or farther from melt, say buying at $1 per ounce under and selling for $1 per ounce over.
These "art bars" came out first in the early 1970s. By 1973 they were a rage. Before that, silver plaquettes, medals, etc., served a limited purpose. When silver rose in price, silver art bars became a fad in numismatics as well as among the conservative right, there being some overlap. Watergate, Elvis, Marilyn, trains, cars, guns, and hundreds and hundreds of variations of American coin images, Eagles and Liberties and Buffalos by the ton.
Anticipating a total meltdown of the U.S. and global economies, the collapse of fiat under the strain of runaway inflation, many of these were called "units." Internation Trade Unit, One Trade Unit, One International Unit, etc. They were just ounces.
Dozens, if not a hundred, ad hoc "mints" sprang up. The U.S. Mint actually went to court -- through the Federal Trade Commission, I believe -- to have the word "Mint" legally reserved for their exclusive use. That did not work.
Some of these bars were hawked as instant rarities for as much as $30 each when issued -- which (benchmarked against gasoline) would be like $300 now.
The bubble burst.
Bars are still made because they are pretty and, hey, the Tulip Craze ended and we still have tulips. So, Silvertowne, among others, still makes bars for anniversaries, Christmas, Graduation, etc.
Collecting by Mint is possible. I collect by themes myself. I collect one ounce silver bars from banks. I also like Western themes and there is no shortage of those. I have several different kinds commemorating the Texas Rangers.
My best buy was a Martha Mitchell on the Telephone. That and the Watergate Water Bug both bring nice prices even today.
Engelhard's "Prospector" rounds, the Monex rounds, etc., continue the tradition. Most collectors do not know that the Engelhard "Prospector" was cribbed from a US coin. The US Mint chased the Washington Mint for making Sacagawea replicas, but some animals are more equal than others. (Speaking of animals, I did not know that female mooses had those big antlers.)
By the way -- or "buy the weigh" -- not all one ounce bars weigh one ounce. Weigh the bar. Many of the more reputable run measurably over 31.1 grams per ounce. This error on your side is their way to underwrite your risk. However, I find that the so-called "patriotic" bars are sometimes light, as are other "nice" bars.
Also, you need to be sure that the bar is .999 fine and not sterling .925 fine.
There is a Silver Art Bar collector society that is an ANA member club:
Contact
Solano Silver Round Club
c/o/ Jan D Henke
1806 San Jose Pl
Fairfield , CA 94533-0518
A non-ANA club is the International Association of Silver Art Collectors. Click here:
http://www.rivercitycoins.com/iasac.htmlThis old COIN WORLD article has more detailed information:
http://www.coinworld.com/news/110303/BW_1103.aspSilverTowne is a primary producer. They work under contract. They have stock designs. They are an ANA member dealer.
http://www.silvertowne.com/I also collect aviation materials and I have a couple of art bars with airplanes on them. However, more important are the older medals, also in silver, commemorating airports, aviators, and plane. Those come from before 1972.
I have a short article about silver art bars on Coin Newbies:
http://www.coin-newbies.com/articles/silver_bars.html