Fig. 2

Micrographs of a transverse section of Qitai silicified wood. Bright interference colors are due to a larger thickness of the section than the conventional 30 μm. (a and b) The silicified wood substrate (brown), quartz and calcite crystals (colorless) coexist in the sample. Transmitted and polarized light. (c and d) Quartz-enclosed wood substrate. Transmitted and polarized light. (e and f) Transition region of the inner silicified wood substrate, large quartz grains with euhedral terminations and outer calcite. Polarized light. SW = silicified wood, Cal = calcite, Qtz = quartz, CS = cellular structure.