"Popped" Asteroceras obtusum ammonite fossil (68 mm)

"Popped" Asteroceras obtusum ammonite fossil (68 mm)A stunning example of a calcite ammonite fossil of the species Asteroceras obtusum from the world famous Jurassic Coast beach of Lyme Regis, Dorset UK. The ammonite sits inside the original piece of limestone matrix in which it was found, that has been split open to reveal both the positive and negative parts of the shell. The main piece of matrix measures 180 mm (7. 1 inches) across and the fossil ammonite measures 68 mm (2. 72 inches) across. The

A stunning example of a calcite ammonite fossil of the species Asteroceras obtusum from the world-famous Jurassic Coast beach of Lyme Regis, Dorset UK.

The ammonite sits inside the original piece of limestone matrix in which it was found, that has been split open to reveal both the positive and negative parts of the shell. The main piece of matrix measures 180 mm (7.1 inches) across and the fossil ammonite measures 68 mm (2.72 inches) across. The ammonite is well preserved and has been prepared out of the rock to reveal the whole shell. Part of the outer whorl has some unusual crushing, making it flatter than normal. This likely happened during the fossilisation process.

This is what is known as a "popped" ammonite, meaning that when the rock split, both the positive shell and cast in the matrix were revealed. The ribs are very finely defined and the deep brown colour is beautiful, especially with the pale suture lines contrasting against it. The two pieces of matrix fit back together, hiding the surprise within, and the main piece has a cut-flat base to allow it to be displayed free standing. 

 A great example of the species and impressive in the flesh. Both piece of matrix weigh 1515 grams together. These are very sought after ammonites from this world-famous location.

Around 196 million years old (Sinemurian, Early Jurassic), this fossil would make a wonderful addition to any collection.