When sourcing Ginseng Powder, the primary quality indicator is the Ginsenoside content, which should typically range from 3% to 80% depending on whether it is a straight powder or a concentrated extract. Buyers must request a Certificate of Analysis (COA) for every batch to verify the absence of heavy metals (Lead, Arsenic, Mercury) and pesticide residues, ensuring the product meets USP or EP standards. Additionally, distinguish between White Ginseng (air-dried) and Red Ginseng (steamed), as the latter often commands a higher price due to its enhanced bioactive stability.