Ash (sodium carbonate) sometimes appears on soap while it is in the mold, or while it is curing. It is supposed that the alkali in the soap absorbs the carbon dioxide in the air, forming sodiaum carbonate/soda ash on the soap. The ash appears inconsistently. It can appear on only part of the surface of the soap in the mold. It can sometimes appear after a soap is unmolded, and then only on some surfaces of the bars. The carbon dioxide in the air is constant. The alkali and the oils in the soap have already begun saponification. Many live in highly humid areas and do not get ash on their soaps. What does the appearance of ash depend on? If someone can help with this, it would be greatly appreciated by many who make soap. Thanks very much?