Vc is cheaper, generally using levorotatory vc, which is easy to absorb. Pearl powder is more expensive, and there are many cheaper ones on the market. It's usually fake, and it's clam shell powder, which smells a little fishy. Both vc and pearl powder can be taken orally or used externally. They can be mixed with honey and used as facial mask, or mixed with cotton facial mask cream. However, mask cream is a chemical substance with unstable properties. It is best to use it alone or eat it. Suggestions.