This fossil ammonite has been lightly polished, and you can see some flashes of red iridescence! It comes from Majunga, Madagascar and is discreetly and permanently attached to a gold coloured stand.
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 1/16 inches (2.7 cm) wide, 9/16 inch (1.4 cm) deep and 7/8 inch (2.2 cm) tall.