Carbon 14 radiometric dating
These plants take up silica from the soil, whereupon it is deposited within different intracellular and extracellular structures of the plant. Although some use "phytolith" to refer to all mineral secretions by plants, it more commonly refers to siliceous plant remains.
In contrast, mineralized calcium secretions in cacti are composed of calcium oxalates.
Optical microscopes with magnifications of 200-400x are typically used to screen phytoliths.
Scanning electron microscopy may also allow for a more detailed study of phytoliths.
Phytoliths may also provide plants with protection.
First, soluble silica, also called monosilicic acid, is taken up from the soil when plant roots absorb groundwater.Taxonomic resolution issues deriving from the multiplicity and redundancy problems can be dealt with by integrating phytolith analysis with other areas, such as micromorphology and morphometric approaches used in soil analysis.It is suggested that using phytolith data from food residues (on ceramics, usually) can decrease the bias from both of these problems, because phytolith analysis is more likely to represent crop products and identification of phytoliths can be made with more confidence.Such immobilised elements, in particular carbon, are valuable in that they permit radiometric dating in reconstructing past vegetation patterns.The silica in phytoliths has a refractive index ranging from 1.41 to 1.47, and a specific gravity from 1.5 to 2.3.