S.C. Code Ann. § 12-21-5080: Quantity measured by weight or dosage; diluted quantities.

For the purpose of calculating the tax under Section 12-21-5090, a quantity of marijuana or other controlled substance is measured by the weight of the substance whether pure, impure, or dilute, or by dosage units when the substance is not sold by weight, in the dealer's possession. A quantity of a controlled substance is dilute if it consists of a detectable quantity of pure controlled substance and any excipients or fillers.