Summarize:

Commodities are raw materials, agricultural products, petroleum products, and industrial and precious metals. Physical commodities are bought and sold in bulk for immediate delivery in specialized markets around the world. These markets are known as the "spot" or "cash" market. The majority of participants in the spot market are producers, and users of the commodity, able to finance and store large amounts of a commodity such as a refinery buying crude oil or a flour miller buying wheat and corn. As a consequence, individual investors rarely purchase any physical commodity except precious metals like gold, silver, platinum. or palladium. An individual taking delivery of a physical commodity must be prepared to:  Pay a premium over the spot price, whether purchasing coins or bullion. Premiums can range up to 25% of the spot prices. Pay cash for the total purchase price. If an investor wishes to leverage his purchase, he must find and negotiate with a private lender who is willing to accept the metal as collateral. Pay extra charges for storage and insurance to protect against theft. Assume the risks of illiquidity. Finding a buyer for a large amount of gold, for example, might be difficult and expensive You can buy physical commodities by visiting specific websites or exchanges where they are sold. They are not available through standard brokerages. Finding reputable markets to buy in can be difficult, however. Look for well-known authorities to point you towards safe places to trade physical commodities. For example, the World Gold Council maintains a list of reputable sites selling gold coins and bullion. Physical commodities need to be stored in secure locations until sale. You can also buy insurance to protect you from a total loss if the commodities are stolen. Both of these increase the cost to the investor and cut into potential gains. Some gold-selling companies offer secure storage for buyers.
Understand physical commodity transactions. Buy or sell physical commodities. Store your physical commodities.