In order to derive a unit a mass from a unit of volume, we need a suitable unit of density in the range of materials encountered by human beings. Water is a material vital to human life, with a density typical of this range. Therefore, Primel recognizes the density of water as its third "mundane reality".
Primel in fact uses the maximal density of water as its coherent unit of density, the ′densitel. This has a value of 999.972d kilograms per cubic meter (or 0.999972d kilograms per liter) and occurs at 3.98d°C = 39.16d°F (equivalent to ᘔ.035z ′stadegrees on the crystallic scale).
This value for the ′densitel leads to a unit of mass, the ′massel, of about 0.55d grams (nickname: ′morsel·mass). This makes for a rather small base unit of mass. However, scaled up three orders of dozenal magnitude, the triqua·massel (nickname: ′hand·mass) is remarkably convenient at just under 1 kilogram and just over 2 pounds.
Because Earth's gravity is the unit of acceleration (1 ′accelerel = 1 ′gravity), whatever the mass of anything is in ′massels, the force of its weight in ′forcels (or ′weightels) will be numerically the same (more or less, given the latitudinal variation of gravity on Earth). So we could easily speak of the mass of something in ′morsel·masses or ′hand·masses, and its weight in ′morsel·weights or ′hand·weights, using (approximately) the same magnitudes. Contrast this with the situation in SI, with kilograms of mass versus newtons of weight, with the factor of 9.80665d m/s2 in between.
From the ′forcel, in straightforward fashion we can derive units for energy (the ′energiel or ′workel), for power (the ′powerel), for pressure (the ′pressurel), and for the rest of Newtonian mechanics.