Fossil wood is an incredible material that allows us to peer into the deep past of our planet and put together a picture of the prehistoric world. These fossilized wood specimens from Saxony, Germany come in both mummified and permineralized forms.

Mummified wood refers to wood that fossilized without the presence of oxygen and foreign microbes, preserving the inner cellular structure. Permineralized wood is wood that has had its organic material replaced by mineral deposits.

Whether mummified or permineralized, all Sparklewood specimens are infused with druzy crystal inclusions across the surface of the material. They are a beautiful combination of geological processes. Each Sparklewood specimen has been photographed and listed separately. You can see all our currently available Sparklewood in the collection below!

Just as minerals can seep into an animal’s remains and preserve its shape, fossilized wood is an impression of a tree in life, rendered in stone. The process is the same as in other fossilization, beginning with a tree buried in sediment, volcanic discharge, or flooding water.

Once submerged, the organic material is steadily replaced by foreign minerals like silica, calcium carbonate, or iron pyrites through permineralization. Not only is the wood’s shape preserved but also its cellular structure which can then be examined by paleobotanists.

When a piece of fossil wood forms in this way it is said to be petrified, preserving a snapshot of the tree as it lived. Some spots, like the Petrified Forest National Park, are home to innumerable fossilized trees, an entire ecosystem preserved in stone. 

If organic material breaks down before it can be replaced, a cast of the tree may be preserved instead, later filled in with inorganic material in the shape of the tree. These fossils are of less use in speculating on a given tree species, as the inner anatomy of the plant is not preserved.

Fossil wood is said to be mummified when the material is not mineralized during the fossilization process. This is fairly rare as it requires the wood to be protected from microbes and oxygen. Because of this, wood that is dry during fossilization is most likely to be mummified, the material's desiccation producing distorted shapes in the fossil. In these fossil woods, the material's cellular structure remains largely intact, and thus is of great interest to paleobotanists.

Conversely, permineralized wood forms through the permineralization process, where the wood's original organic material is replaced by outside minerals during fossilization. These minerals, usually silica, enter via the wood's pores and steadily replace all the organic matter. This process can produce stunning gemstone-infused specimens of opal, agate, or other silica-based gems.