I don't know that Impression was ever available as a standalone single. The Watercolors set had three softer pastel shades; when blended together, they were fairly invisible. This color works best as a soft blue base color - either over a light base, to provide a glaze of soft blue, or over a dark base to emphasize the shadow itself. It's a matte color, so it can be layered underneath eye quickies, mica powders, or other iridescents.
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