Editing Voynich manuscript (section)

=== Ink ===
Many pages contain substantial drawings or charts which are coloured with paint. Based on modern analysis using [[polarized light microscopy]] (PLM), it has been determined that a [[quill]] pen and [[iron gall ink]] were used for the text and figure outlines. The ink of the drawings, text, and page and quire numbers have similar microscopic characteristics. In 2009, [[energy-dispersive X-ray spectroscopy]] (EDS) revealed that the inks contained major amounts of carbon, iron, [[sulphur]], [[potassium]] and calcium with [[trace element|trace amounts]] of copper and occasionally zinc. EDS did not show the presence of lead, while [[X-ray diffraction]] (XRD) identified potassium [[Lead(II,IV) oxide|lead oxide]], potassium hydrogen sulphate, and [[syngenite]] in one of the samples tested. The similarity between the drawing inks and text inks suggested a contemporaneous origin.<ref name=analysis />