The outer side of the upper leaf has a pin gnomon dial (pin missing) for common hours marked 1 to 12 twice, and coloured in green, red and blue. This decoration is also on the border and there are concentric circles in the centre.The inner side of the upper leaf has the same pattern and an unequal scale for latitudes on the right, marked in red from 0? to 80?, divided to 1? and numbered by 5?.
The inner side of the lower leaf has a compass bowl with paper compass card, silvered and painted, and a horizontal string gnomon dial for common hours marked 5 to 12 to 7. The same decoration as in the upper leaf is on the borders. The arm for adjusting the latitude is on the right side and on the left edge of the leaf is the compartment for stowing the pin.
The same geometrical decoration is on the edges and on the outer part of the lower leaf.
See P. Gouk, The Ivory Sundials of Nuremberg 1500-1700 (Cambridge, 1988).
Ilaria Meliconi