Figure 7. Phosphatized wood. (A,B) carbonate-fluorapatite, Virgin Valley, Nevada, USA, Miocene, radial view; (C,D) fluorapatite, Santa Fe River, Florida, USA, Neogene, radial view; (E,F) small euhedral apatite crystals on cell walls in carbonized wood, Yuba River, Nevada County, California, USA, Eocene, (E) oblique transverse view, (F) radial view.
Abstract
The best-known and most-studied petrified wood specimens are those that are mineralized with polymorphs of silica: opal-A, opal-C, chalcedony, and quartz. Less familiar are fossil woods preserved with non-silica minerals. This report reviews discoveries of woods mineralized with calcium carbonate, calcium phosphate, various iron and copper minerals, manganese oxide, fluorite, barite, natrolite, and smectite clay. Regardless of composition, the processes of mineralization involve the same factors: availability of dissolved elements, pH, Eh, and burial temperature. Permeability of the wood and anatomical features also plays important roles in determining mineralization. When precipitation occurs in several episodes, fossil wood may have complex mineralogy.
Full paper is available for download.
https://www.mdpi.com/2076-3263/8/3/85