This faux lapis lazuli panel was completed for a specific client. Lapis lazuli is a semi-precious stone (not a marble) and ultramarine blue is made from it.
Non-colors (achromatic colors) are essentially black and white. When mixing a color, these non-colors are only used to change the intensity and opacity of a color. It is best to avoid using too much of either black or white and rather try to rely on colors first and add them only at very last bit to get color for a final tweeking.
When you are looking at a large room and say, "where do I begin?", this post will tell you in what order to paint an entire room. On this diagram below, the
