Meet the solution to pigmentation, excess sebum, and pore problems ? the Tia?m Pore Minimizing 21 Serum! The sleek black bottle houses a formulation that features 21% of niacinamide and 1% of zinc PCA to improve the appearance of pores, lessen sebum production, and fade dark marks. With niacinamide being one of the most studied ingredients, you can trust that this bottle will help prevent blemishes (and more).