In my opinion... Fake; a poorly executed attempt at a Qianlong guanyao six-character seal mark in zhuanshu script (zhuanshu is the special seal-form script). It doesn't look as though it's an iron red enamel reign mark over the glaze but simply a factory stamp. You would be better able to tell, having the item in front of you.
Forgery for the western market, I'd say - but get it checked by an expert rather than an amateur (as I am) to be sure. It's such a collectable period but fraught with difficulties for even informed collectors.
