Prolong your makeup with the bareminerals prep step mineral shield spf50 an antioxidant primer for all skin types perfect for those who want to protect their skin from pollution and external aggressors the bareminerals prep step mineral shield spf50 helps to defend your skin from premature aging and sun damage whilst prolonging your makeup base this mineral based primer contains colour adaptive pigments that blend beautifully into your skin ensuring your foundation coverage is left smoot