Mountain of Ink recently did a very thorough review of Herbin Eclat de Saphir ink. She describes the color:
Eclat de Saphir is a vibrant blue-purple or blurple.
She did swab and splatter samples to show the shading of the ink. She shows writing samples with extra fine, fine, medium, broad, and flex nibs plus drying times on Rhodia, Tomoe River, and Leuchtturm papers. She shows comparison photos of the color with several other blue inks. She also shows a longer writing sample. She sums up her experience of Eclat de Saphir:
Overall, I really enjoy this ink. It has a nice flow, gorgeous color and dries quickly.
Herbin Eclat de Saphir is available at Goulet Pens and other fine retailers.