Physician's Formula Gel Eyeliners have become a staple in my stash.  I've picked up several of these trios, which you can see swatches of here.  The black(s) in these trios are my go-to eyeliner.  I tend to lean towards gel and or liquid liners vs. a pencil because I have an easier time applying them, and I feel like they stay put better than a pencil.   The Physician's Formula Shimmer Strip Custom Gel Eyeliners are no exception - not only are they all extremely pigmented, but they apply so easily and last all day without budging.  

Today I have closeups of the Glam Eye Collection for Blue Eyes.  This set includes a pure silver, cobalt blue shimmer and black with just the slightest hint of silver shimmer, although I don't think it translates onto the eye so much.   

Below are the swatches, using the broad side of my flat eyeliner brush.  I was surprised at how nicely the silver covered.  I assumed this would be a bit more sheer, but this is actually a nice depth of color, so it covers very well.  If you used a lighter hand, it could be applied over the black to give it a more graphite shade, but alone it is strictly silver.  The blue is a true, cobalt blue, and the black is just that...black.  You can see the silver shimmer in the swatch below much better than on the eye, but that's probably because it's a broader application. 

Have you tried these?  What is your favorite set?