To be able to handle minute quantities of liquid mercury or liquid mercury lloy, for example to introduce said minute quantities into the discharge vessel of a discharge lamp, a retention body in form of a pill or pellet is formed which is a porous of a metal or mixture of metals or metal alloys which have a melting point above 250.degree. C., are not wetted by mercury, and do not form an alloy with mercury. To make such a body which, for example, is made of iron, iron and copper--to reduce oxidation, nickel and copper or iron, chromium and possibly also nickel, a metal salt of the respective metal is electrolytically enriched with mercury to form a mercury--metal suspension; in case of several metals, the suspensions are mixed, coated with aqueous-free glycerine, tempered, washed, dried, non-absorbed mercury is filtered off, and the resulting filter cake is pressed out at high pressure, of 5 to 60.multidot.10.sup.7 Pascal; the brittle pressed body is pulverized and pellets of dimensions of about 1.5 mm by under 0.5 mm height are formed as press bodies, the mercury content of which can be controlled within suitable ranges by controlling the pressing-out pressure.