This is an unpolished ammonite, Perisphinctes sp., from Madagascar. Ammonites are are an extinct group of marine molluscs which date from the Devonian about 350 million years ago.

 The specimen measures 2.11 inches in diameter. The suture lines on the specimen are raised and  well-preserved. The ammonite is a golden and creamy-white color .

All of my fossils are guaranteed authentic and have been legally obtained.