Masks are an advanced part of anyone's beauty regime. Often overlooked by novices or the time-strapped, masks can be viewed as a "booster shot" for your skin - especially during the times where you are stressed and the skin pumps out extra oil and increases skin cell turnover to compensate.
Masks can perform a variety of services that benefit your skin. For instance, some masks might be used to exfoliate the layer of dead skin to clear your pores, and then will attach itself to any blackheads underneath that you may already have. Once you roll the gel off your face, it will help pull these blackheads out of your pores and voila! Your blackheads have been dissolved, leaving you with clear, smooth skin.
These kinds of masks clean deeper than just a regular facial cleanser would normally go, which is merely scrubbing the top surface layer of the skin - fine for some purposes, but when you're talking about a deep clean that scrubs out the pore impurities that cause blackheads, a surface cleanser just won't do. Tea tree is an important element in these masks because it helps to liquify the waxy buildup that can leads to the formation of a blackhead.
Masks can also come in a clay base. Once applied, the mask dries on the skin, and once washed off, removes all of the dry skin cells with it. This enables your skin to "breathe" again.
Masks should be applied on a consistent weekly or bi-weekly (twice a week) basis in order to keep your skin clear of the daily impurities that can build up in your pores. If you have sensitive skin, however you need to be wary of using a mask too often, as it can irritate skin that is prone to irritation. Mask users must also take note if they see an increase in oil production, as over-usage of a mask can over-stimulate pores into producing more oil.