The mortar and pestle has no single documented point of origin because it does not need one: grinding tools of this basic two-part design are attested across essentially every ancient culture that processed minerals, grain, herbs or pigments, arising independently and repeatedly wherever people needed to reduce a hard solid to a fine powder. Its ubiquity is exactly why it belongs in this category without a named inventor: unlike the alembic or the aludel, which can be traced to a specific tradition and a specific centuries-old transmission, the mortar and pestle was already old and universal by the time any alchemical text was written down, a background tool so basic it rarely warranted description at all.
In an alchemical laboratory it served as the standard preparatory step before nearly every other operation, grinding a mineral, a metal filing, or a dried herb fine enough to dissolve, calcine, or sublime evenly. It is one of the very few instruments in this whole category that needed no reinvention whatsoever to remain in constant daily use: a mortar and pestle sits in chemistry and materials science laboratories today for exactly the same grinding job, sits in most kitchens for crushing spices, and remains, worldwide, the literal professional emblem of the pharmacy trade.