Abstract: A method and apparatus for quantifying volume of a deposited skin-print A method of determining a volume of skin-print residue deposited on a substrate is disclosed. The method comprises: performing interferometry on the substrate with skin-print residue deposited thereon to determine raw topography data of the substrate including the skin-print residue. The method also comprises: processing the raw topography data including subtracting topography of the substrate without the skin-print residue from the raw topography data in order to determine skin-print residue topography data. The method further comprises: determining volume of skin-print residue deposited on the substrate from the skin-print residue topography data.