Pyrite Crystals in the Parenchyma Cells in Wood of Fossil Root

Abstract

VERY small octahedral crystals (1 micron–20 micron) of iron pyrite have been found in the ray and wood parenchyma cells in parts of a fossil root of Oligocene age. The black humified wood is elsewhere partially replaced by veins of pyrite, as commonly seen in fossil wood of this sort. The wood, illustrated in Figs. 1 and 2, was taken from one of many roots observed in the Hordle Cliff section of the Lower Headon beds near Milford-on-Sea, Hampshire. Similar roots occur in exposures of these beds at Totland Bay, Isle of Wight, and in both places the roots are in the position of growth¹. All the wood that we have examined anatomically is of a single type and, although some of the finer diagnostic features are not well preserved, it is closely similar in structure to the wood of Taxodium distichum (swamp cypress). We cannot, however, ignore the possibility that the roots belonged to the Tertiary Sequoia couttsiae which is prominent among the plants identified from other remains in the Lower Headon beds². A full description and discussion of the identity of our material will be presented elsewhere.