The problems posed by the need to consider angular shapes in order to achie
ve more realistic micro-mechanical models of rock particulates are introduc
ed. A relatively simple and fast particle deposition algorithm for packing
simulations is developed. The details of the algorithmic procedures for dep
osition of tetrahedron-shaped particles of different size and aspect ratio
are outlined. Numerical results including predictions of porosity for spher
es, tetrahedra, different particle size distributions, binary mixtures and
tetrahedron shapes are presented. For the loose packing of spheres extrapol
ated to zero wall effect, the porosity obtained was 0.414. Mono-sized tetra
hedron packs with wall effects for a 3.288 cm edged equilateral tetrahedron
packing in a 30 x 30 x 30 cm box produced an average porosity of 0.627 wit
h a value of 0.584 when extrapolated to zero wall effect. Binary mixtures o
f tetrahedra show the characteristic minimum in porosity for a size mixture
. The minimum is less well defined than for spheres. Continuous size distri
butions of tetrahedra based on a truncated Schuhmann distribution from 0.28
to 2.8 cm edge length in a 10 x 10 x 10 cm box do not indicate that distri
butions with a lower uniformity will necessarily produce a minimum in poros
ity. For tetrahedra of constant volume the porosity increases with decreasi
ng sphericity in tetrahedra with different aspect ratios.