I presume that you will take precautions when you carry such a thing. But there are a few potential flaws. When you glue the crystals to the vial, you reduce the surface plus there might be too much glycerin. I`d pack the crystals and the vial into a small plastic bag and seal it. Wrapping or jamming the vial into cotton fibres might make ignition difficult. So it might be required to fluff it.