<p>Workshops located on the slope of the <i>collis Quirinalis</i> (*Quirinal) between the Temple of *Quirinus and Temple of *Flora where mercury ore imported from Spain was refined to produce <i>minium</i> (cinnabar, a red pigment; Vitr., <i>De arch.</i> 7.9.4; Papi; Rodríguez Almeida 52-54). This artisanal process is described in some detail by Pliny (<i>NH</i> 33.118-20). The workshops were probably established during the second half of the 1st c. B.C. (Papi). Though mentioned by both Vitruvius and Pliny, neither author preserves the ancient name of the workshops. Current scholarship typically employs the name “Officinae Minii”; however, Papi suggests that “Officinae Miniariae” may also have been a valid label (based on <i>CIL</i> VI 9634).</p>