A silver certificate is a type of paper currency issued by the US government from 1878 to 1964. They are similar to regular banknotes, but they are backed by silver bullion instead of gold. The value of a silver certificate depends on the face value, condition, and rarity of the note. Common silver certificates are worth only a few dollars over their face value, while rare or well-preserved notes can be worth hundreds or even thousands of dollars. The value of silver certificates is assessed by reputable grading services such as the Professional Coin Grading Service (PCGS) and the Numismatic Guaranty Corporation (NGC), which authenticate and grade the notes.