66MM Pygurus Marmonti Sea Urchin Fossil Sand Dollar Jurassic Age Madagascar

Location: Majanga, Madagascar

Weight: 4.3 Ounces

Dimensions: 66MM

The item pictured is the one you will receive.

Pygurus marmonti, commonly known as a fossil sand dollar or fossil sea urchin, is an extinct echinoid species dating back to the Jurassic Period, approximately 145–200 million years ago. These marine invertebrates lived in shallow ocean environments where they burrowed into soft sediments, contributing to the dynamic ecosystems of ancient seas. Their preserved fossils, especially those discovered in Madagascar, are prized for their symmetry and detailed preservation.

The fossilization process began when the sea urchin’s hard shell, or test, was buried beneath layers of sediment shortly after death. Over millions of years, mineral-rich waters replaced the original materials, creating durable stone replicas that retain the intricate five-pointed star pattern characteristic of echinoids. Natural polishing through geological processes often enhances surface details and reveals the fossil’s striking geometry.

Today, Pygurus marmonti fossils are admired both for their scientific value and their natural beauty, offering insight into Jurassic marine environments while serving as elegant examples of prehistoric life.

Please be aware of the nature of fossils:

Being buried under the ground for millions of years under tons of pressure tends to be rough. No fossil comes out of the ground whole and perfect. Most fossils have undergone some restoration, while others are altered by man simply to enhance their presentation in different ways. The workers in Madagascar do a very professional job of unearthing and preserving these natural treasures; however, natural cracks are visible on the surface. These are part of the natural beauty of the fossil and are not considered defects.