"TRANQUILITY" -Photograph of crystalline citric acid found in citrus"Tranquility" has a tropical flare with a stunning mix of of botanical colors. Citric acid which is found naturally in citrus fruits was crystallized by evaporation on a glass microscope slide, then photographed through the microscope. The crystal facets create the colors naturally by refracting transmitted white light, separating it into the colors of the spectrum.