What is the "white discharge" (al-qassah al-bayda') that must be considered, the pure white or the transparent, and are transparent discharges mixed with whiteness considered the "white discharge"?

The signs of purity from menstruation are dryness or the white discharge. Dryness means the place is dry when a cotton swab is inserted, with no trace of blood, yellowish discharge, or brownish discharge, and the presence of normal secretions does not matter. As for the white discharge (al-qassah al-bayda'), it is a white fluid that emerges after menstruation, resembling plaster water, dough water, or semen, and it varies according to women and circumstances. If a woman sees one of these two signs, ritual bathing (ghusl) becomes obligatory upon her.