Septarian Freeform- Madagascar For Sale

Septarian Freeform
Madagascar
Dimensions: 7.6 x 6 x 4.6 cm

This is the exact item you will receive. 

Septarian is less a single mineral than a geologic structure—specifically, a type of concretion that developed internal cracks which were later filled by minerals. That distinction is useful because a lot of material sold simply as “septarian” is actually a combination of several minerals:

• Yellow to honey-colored material: commonly calcite
• Brown/tan material: commonly carbonate-rich concretion material, frequently described as aragonite in the trade
• Gray/black material: sedimentary limestone/marl or clay-rich matrix