Maybe Chrysocolla..a sharply colored mineral. Its color can be among the brightest shade of blue and green, and is caused by its copper content. Chrysocolla is often coated by a drusy layer of glossy clear Quartz, or intergrown together with the Quartz.
The chemical formula for Chrysocolla is not clearly defined, as it contains a varying substitution of elements and water content in its chemical structure. Though a more definitive form of Chrysocolla with an identifiable chemical formula can exist in microcrystals, most forms are considered amorphous. Multiple analyses of different compositions have been offered over the years.
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