MAC Cast Iron is a very cool-toned, dark blue with a satin finish. It is a permanent eyeliner that retails for $17.00 and contains 0.012 oz.
MAC Cast Iron Technakohl Liner ($16.00 for 0.012 oz.) is described as a "elephant grey." It's a muted, bluish-gray with a satin finish. It was waxy and sheer, though I was able to build it up to semi-opaque color coverage with several passes. It wore well for seven hours before it faded. At least this shade was more unique, though the formula is still disappointing. See comparison swatches / view dupes.
The liner’s enduring formula features a unique combination of plant-derived waxes, providing a soft, comfortable feel, while staying smudge-resistant for up to eight hours. Whatever your style, get ready to line it up.