Both paper and physical silver rely on the comex pricing as of this post in early October 5, 2011. The free market for the paper game is the rules that are associated within' the brokers you are associated with and pretty much Wall Street. The free market in the physical game will use the comex price as a reference and then decide what premium to use from the spot price. Therefore the same chart you use like the one above is useful for both positions.
Physical is just that. Forms of physical are 999 fine rounds/bars that are at least 99.9% pure silver (hens the 999), can be in many forms of Stirling (925, 92.5%) and practically all countries in this world had silver between 40% to 92.5% in their circulated coins in the sixties and earlier. There are other forms like jewelry and the category misc. where the value is set on the scrap melt value as well as any numismatic value.
People often call SLV and futures to be that of paper and I don't see why we would. Computers have taken over and at least with paper you have something that has some scientific value. Silver and Gold are universal within' metals on the periodic table and therefore it is not paper at all but digits and data sets in computerized technology. Maybe you can request to get paper shares of your SLV and they may comply to your wish(maybe) and if you ask for some bars or coins, you ain't getting any. Therefore you are only getting numbers on a database.
When you sell silver coins or bars on the physical level you can sell for many different things. You can sell your silver for fiat cash or paper rectangles or you can sell it for gold or food or a car or real estate and I could keep going on with products and services they can be used for within' barter. If silver is not a common trade in the economy one is in (like the current) then sometimes you have to trade them for paper rectangles first. Therefore if you bought silver for a total for $4,000 years ago for your lot and sell it today for $12,000 then you turn around and buy a car with the $12,000 then you turned your investment into a car during the tenure you were holding the physical.
When you sell SLV Shares or futures contracts or even shares of miners then you can only sell for the currency level and the funds are sent to your account. If you want physical delivery of your paper rectangles then you have to demand delivery some how by going to bank or ATM. The point is you have no choice but to turn what your silver is worth into something else in a currency collapse. If SLV goes to 210.43 a share when you cash out then you need to turn this into something real before the currency dies. If you cash out of SLV and get yourself what you need to survive and thrive in real goods and you do this successfully then congratulations but it will most likely cause headaches when you have a bank holiday threat.