Abstract: Stains and methods of forming stains comprising saturated hydrochloric acid solutions of blended metallic salts that are chemically reactive with masonry concrete, stone, and like materials. The concentrated stains produce a full spectrum of colors derived from earth elements in the metals and transition element group, and from ores, and refined chemicals. Groups of concentrated mixtures emphasize the colors black, yellow, cyan and magenta to produce an overall earth-tone color. By separately dissolving each heavy metal constituent in an acid solution to the point of total saturation or crystallization, and then adding these mixtures to a predetermined base acid mixture, a stable, concentrated stain results. The individual ingredients are blended to produce a chosen color spectrum by adjusting mixture proportions.