Ed Jelley recently did a great review of the new Herbin 1798 Anniversary ink Kyanite du Nepal, which is a bright turquoise with silver shimmer and is coming out this month in the USA! Check out his review here for lots of photos of the ink, with writing samples showing the shading and shimmer. Be sure to click on the photos in the Gallery at the bottom of his post and zoom in so you can really see the details!
He describes the shading and sheen:
When writing (okay, it’s more like playing) around with a folded nib dip pen, the ink exhibits some nice shading and variation in tone. Both dark and light shades of turquoise are visible, with extra sheen in the areas where the ink goes down thicker. There’s just a tiny little hint of red sheen around some edges. I wouldn’t count on seeing that regularly unless there’s a LOT of ink on the page.