A salver is a flat tray used for carrying drinks or food to a table. Salvers are also known as card trays. These items are collectible.
The first silver salvers appeared in the last half of the 17th century. They were small circular trays used as stands for large silver tankards. Salvers from this time period are quite rare. The first mention of a salver is in 1661 where it's described as "...a new fashioned piece of wrought plate, broad and flat, with a foot under neath, and is used in giving beer, or other liquid thing to save the Carpit or Cloathes from drops."
Early models were generally simple in design and without any decoration. The later models had engraved borders or a coat of arms engraved in the center. Early engraved silver salvers do exist but they are very rare.
A notable type of salver called the Chippendale was introduced during the time of George II (r. 1727-1760). They were called Chippendales because the borders were reproduced from the rims of tables designed by cabinet maker Thomas Chippendale. Chippendales and other salvers came in a great variety of styles and shapes that included square, circular, oblong, and irregular shaped.
The earliest salvers were made of silver. Some of the later models were made of Sheffield plate or silver plate.
Value
Antique silver salvers are rare and they can sell for hundreds of dollars. Some early pieces can sell for over $1,000. Antique silver plated pieces can sell for over $100.
Sources:
The Book of Old Silver