That's likely an inexpensive aftermarket mirror. Save yourself some time and a destroyed mirror with a possible blood sacrifice. Buy another one.
It's my personal experience that most eco mirrors will vibrate at different rev ranges. On my '81's similar matte black mirrors, I have added small, round, stick-on wide angle mirrors that are very helpful in reducing the "armpit mirror check" image that the narrow euro bars help create.
I bought benuine BMW-sourced mirrors for the R100S that are totally vibration free. Motobins sells the Bumm brand mirrors used by BMW Motorrad. Far less expensive than from my local stealership.