A fossil ammonite from Madagascar. It has been polished to show the warm browns of the calcite that preserved it. You can see the suture patterns on the surface from the walls (septa) dividing the different internal sections of the shell. The sutures can be very intricate, and vary with different species of ammonite. The specimen is discreetly and permanently attached to a silver coloured stand. This is a large ammonite in 1:12 scale, a 6" equivalent in 1:6 scale.
Ammonites are extinct relatives of modern day nautiloids and squid. The largest known ammonite in the world would have been 8 1/2 feet (2.59 metres) across if it were complete.
1 1/4 inches (3.2 cm) wide, 1/2 inch (1.3 cm) deep and 1 inch (2.5 cm) tall.