Mazon Creek Fossil Calamites Leaf Annularia Carboniferous Plant Fossil Illinois USA Authentic

Description

Mazon Creek Fossil Calamites Leaf – Annularia

This listing offers a genuine Mazon Creek fossil specimen of Calamites leaf whorls known as Annularia, preserved in siderite concretion from the world-famous Mazon Creek Lagerstätte in Illinois, USA. Dating back to the Carboniferous Period, approximately 307–309 million years ago, this fossil captures a detailed record of one of the most iconic plant groups of the ancient coal-forming forests. As with all of our specimens, it is 100% authentic and comes with a Certificate of Authenticity. The photos provided show the exact fossil you will receive, and a 1 cm scale cube is included for accurate sizing.

Geological and Historical Context

The Mazon Creek fossil beds are among the most scientifically significant fossil localities in the world, celebrated for their exceptional preservation of both plant and animal life. These fossils are found within siderite nodules deposited in the Francis Creek Shale Member of the Carbondale Formation, dating to the Pennsylvanian subperiod of the Carboniferous.

During this time, lush tropical wetlands covered much of what is now Illinois. Seasonal flooding, rapid burial, and chemical conditions unique to the environment created the perfect setting for preserving delicate plant tissues that would otherwise decay rapidly. This remarkable process has made Mazon Creek a Konservat-Lagerstätte, or site of extraordinary fossil preservation.

Fossil Plant Identification

The fossil offered here is an Annularia, the leaf whorl of the extinct genus Calamites, a relative of modern horsetails (Equisetales). Calamites were towering tree-like plants that could grow up to 30 meters in height, forming dense thickets in the swamp forests of the Carboniferous.

• Order: Equisetales
• Family: Calamitaceae
• Genus: Calamites
• Leaf Form: Annularia

Annularia fossils are characterised by radial whorls of slender, pointed leaves, often preserved in beautiful starburst-like arrangements. These leaves grew in circular clusters along the segmented stems of Calamites, giving them a distinctive appearance easily recognisable in the fossil record.

Morphological Features

This specimen preserves fine venation and leaf arrangement, with the whorled pattern of Annularia clearly visible. The radiating leaves provide excellent insight into the growth structure of Calamites, which relied on rapid vertical growth to compete for sunlight in dense Carboniferous forests. The siderite concretion has split cleanly to reveal both part and counterpart, allowing detailed study of the fossil’s natural form.

Scientific and Collector Significance

Mazon Creek fossils are highly valued for their clarity, rarity, and historical importance. Annularia fossils in particular offer a glimpse into the vast swamp ecosystems that would eventually form the world’s coal deposits. They hold great importance in paleobotany, helping researchers reconstruct ancient environments and understand plant evolution during the Carboniferous.

For collectors, this piece is both scientifically valuable and aesthetically appealing, with the star-like whorls of Annularia making it one of the most attractive and sought-after plant fossils from Mazon Creek. It is an excellent specimen for display, teaching, or research, representing one of the most iconic fossil localities in the world.

Provenance and Authenticity

This fossil comes directly from the Mazon Creek area, Illinois, USA, a site legally collected and globally renowned for its fossil preservation. The specimen has not been altered or enhanced beyond careful preparation, ensuring its authenticity. Each purchase includes a Certificate of Authenticity, guaranteeing that this is a genuine Carboniferous fossil plant.

This Mazon Creek Calamites Annularia fossil is a rare opportunity to own a piece of Earth’s deep history. With its combination of scientific significance, beautiful preservation, and renowned provenance, it is a must-have for serious collectors of fossils, paleobotany enthusiasts, and natural history lovers alike.