As the name suggests this Georgian mahogany naval chart weight was used like a paperweight for holding the ships charts in position. It is rectangular in shape, lead weighted with the original brass swan neck handle. It has a shield shaped cut out  where perhaps the owners initials were to go. There is a good  old repair to the veneer near the corner.
These are difficult pieces to find, but a great historical object.
c1770
It measures 21cm l x 10cm w x 2cm h excl the handle.