New Era Comb D brings together kali mur, kali sulph, calc sulph and silica. In tissue salt use, kali mur is often chosen where there is congestion or thickened skin tissue, kali sulph is traditionally linked with skin renewal, calc sulph is commonly used for blemishes and slow-clearing spots, and silica is the mineral most often associated with skin, hair, nails and connective tissue support.
That combination makes New Era Comb D one of the clearer skin formulas in the range. It is usually chosen for minor skin flare-ups such as roughness, breakouts, cradle cap or dry, scaling patches. The added biotin is also relevant here because biotin contributes to the maintenance of normal skin.
Silica and biotin are often talked about together in skin and beauty supplements, while kali sulph and calc sulph are traditional tissue salt ingredients for skin turnover and clearing. If you want a quick read of what Comb D is doing, that is the simplest way to understand it.