Color Cement Handicraft

by Pedro J. Lemos; Reta A. Lemos

MATERIALS FOR MIXING COLORS are as follows: Two sizes of small sable-hair brushes, a palette knife (or putty knife), several small dishes, a spoon, a fine-mesh sieve, and a piece of glass.

TO MIX THE COLORS proceed as follows: Place a little of the desired color on the glass, to this add dry cement reducing the color intensity to the desired strength. Portland cement being gray will do this harmoniously. To this add a few drops of water until the color is of the desired consistency.

The color should always be tested on a tile surface and dried in the sun to determine final color, adding color or cement to the wet mixture to correct the color. Where a tint of color is wanted a white cement should be added instead of Portland cement.

To produce a plain surface color on tiles, the desired quantity of color is mixed and strained, to eliminate all coarse particles. The mixture may be sifted while dry or strained after the cement has been added.

THE USE OF WHITE CEMENT should be limited because white cement is not as durable as gray cement and because its setting qualities disappear as it becomes older more rapidly than gray cement. If perfectly fresh it can be used with good results and produces a more brilliant color when mixed with the colors than when gray cement is used.

TO APPLY THE COLOR either in the mold or to the surface of the object after it is removed from the mold, the color should be applied with a brush.

AS A TEST COLOR PROBLEM use an incised pattern plaster mold and the colors may be planned for the incised tile as follows: Working from a color sketch, mix up colors to match and after the plaster mold has been water soaked it should be oiled by dabbing the brush up and down on the surface. If the brush is stroked it will not leave enough oil on the surface and the color will stick to the tile. Next drip the cement color from a brush with a shaking motion. The various colors are thus placed in each of the partitions of the mold and after drying for fifteen minutes is backed with a layer of plain cement and sand and allowed to set.

When the tile is released it will contain different colors between the incisions and a thin wash of an additional color may be added to fill the incisions.

COLORS CAN BE MIXED one with another while dry or when wet to produce other shades. Violet will be produced by the mixture of mineral orange and ultramarine blue.

PLAIN SURFACED TILES MAY BE COLORED by pouring in a thin layer of color combined with neat cement and then backed up with a concrete mixture. Mottled and variegated color surfaces may be secured by first spattering or dropping drops of another color into the mold before the color mixture is poured in. Or the plain cement or concrete tile can be removed and covered with a color layer which will be dull or glazed in finish.