It depends on the lash brand. The main difference depends on the brand and their construction process. You'll notice with some silk lashes that they may have higher and a more noticeable sheen. Other than that, they are fairly comparable in terms of look and feel, it depends on personal preference.
More importantly, if you want to add volume to your lashes while looking natural, we recommend finding the right style, length, and pattern that fits your unique eye type, as there may only be minor differences between Silk vs Faux Mink lashes.