The most common form of investing in silver is buying them in the form of bullion bars. Just like gold, it can be stored at home in a safe, or in a safety deposit box at your trusted bank. Your profit will depend on the size of the silver bullion bar you have invested in. The most common silver bars are the 100 oz. troy bars. They weigh 3.11 kilograms or 6.8 pounds. It is the most popular among investors. Aside from the 1 oz., 10 oz. troy bars, 1 kilogram bars, and 1000 oz. troy bars, there are also the odd weight retail bars that cost less due to lack of a good and reputable brand name.