The ReadyProbes Solvent-Resistant Permanent Marking Pen enables solvent-resistant writing on frosted glass microscope slides.  Using the pen on other types of hard surfaces could produce writing that is not solvent-resistent.  When used on frosted glass microscope slides, ReadyProbes Solvent-Resistant Permanent Marking Pen is resistant to most solvents, including alcohols and xylene.  Be sure to let the ink dry before exposing to solvent.