The hypertufa mixes used in the troughs shown.

1 part Portland cement
1 part perlite
1 part sand

1 part Portland cement
1 part sphagnum moss
1 part sand

Material you will need:

Portland cement
sand
vermiculite or perlite or sphagnum moss
rubber gloves
dust mask
container to mix hypertufa mix in
trowel
wire brush
board or other flat surface to work on
plastic bag
chisel or knife
spray bottle
water

Treatment of Trough:

Allow to dry slowly in a shaded spot 3-4 weeks or in big plastic bag with humidity under sun.  Mist with water if needed to keep moist.  The biggest failure in making a trough is trying to unmold it before it has cured long enough.  Brush with stiff wire brush to remove sharp edges and smooth look of poured concrete.  Score sides with chisel or knife.

Recipe for hypertufa-different looks

Granite Look
1 part perlite or vemaculite
1 part cement
2 part peat moss

Porous tufa-like
1 part sand
1 part cement
2 part peat

Limestone look
1 part sand
1 part cement
1 part peat

Granite look II
3 parts perl or verm
3 part peat
2 part cement

Sandstone look
½ part sand
1 part cement
½ part peat