Septarian Nodule Value Guide

Septarian nodules, famously known as 'Dragon Stones,' are fascinating geological concretions that formed 50 to 70 million years ago during the Cretaceous period. These specimens are highly collectible due to their complex internal geometry, created when ancient mud balls dried, cracked, and were later filled by crystalline mineral deposits.

What Is Septarian Nodule Worth?

The typical price range for Septarian Nodule is $25 - $40 based on recent sales. However, values can vary depending on the item's condition, rarity, and other factors such as:

• The clarity and brightness of the yellow calcite crystals significantly impact the $25-$40 price range.
• The complexity and symmetry of the 'dragon scale' cracking patterns across the face of the nodule.
• The quality of the polish and whether the specimen is a full nodule, a sliced pair, or a carved shape.
• The overall size and weight of the piece, with larger Madagascar specimens commanding the higher end of the value spectrum.

How to Identify Septarian Nodule?

• Look for the distinct three-mineral composition: yellow Calcite centers, brown Aragonite lines, and a grey Limestone exterior.
• Examine the surface for the characteristic 'turtle shell' or angular cracked patterns that define true septarian formations.
• Verify the origin as Madagascar, which is known for producing nodules with particularly vibrant yellow calcite crystals.
• Check for a heavy, dense feel typical of limestone and clay-based concretions compared to lighter synthetic imitations.

History of Septarian Nodule

Septarian nodules are concretions that formed during the Cretaceous period, approximately 50 to 70 million years ago, when marine life died and settled to the ocean floor. The decaying organic matter attracted calcium carbonate, forming mud balls. As the oceans receded, these mud balls dried and cracked internally, and later, minerals like calcite and aragonite seeped into these cracks, crystallizing and creating the striking patterns seen today. These nodules are primarily found in Madagascar and Utah, USA.