Cocaine Declared Purity, Perceived Quality, Sales, and Revenues on the Darknet

Background: Purity is a critical factor in illicit drug markets, particularly for hard drugs, as misjudging quality can have severe consequences for users. The information asymmetry between buyers and sellers, combined with users’ inability to verify purity before consumption, complicates decision-making. Methods: This study analyzes 4,161 AlphaBay darknet cocaine listings using Generalized Additive Models (GAMs) to examine the relationship between declared purity and market dynamics. Results: A non-linear relationship emerges between declared purity and factors such as prices, perceived quality, sales, and revenues. Claims of high purity (91–99%) correspond to higher prices, and increased sales and revenues. However, claims above 99% often lead to lower perceived quality. Listings with medium purity (68–86%) generally underperform in both sales and revenue, suggesting limited buyer interest in this range. Finally, independent tests on substance quality conducted by buyers lead to an increase in perceived quality and improved market performance in terms of sales and revenue. Conclusion: While purity partially address information asymmetries, trust–strengthened by user feedback and verifiable signals–remains crucial. Implausible claims can damage a seller’s credibility, and negatively impacting market performance. Since consumers are unable to verify product purity, credible declarations are crucial for maintaining trust in the market.