In an AI economy, the Quartz Consensus Protocol mitigates fake-identity attacks by leveraging a decentralized, tree-based data structure, akin to an orchard's branching network. Each agent maintains a unique, self-certifying identity, linked to a slowly changing, cryptographically secure salt. An attacker attempting to create a Sybil attack must solve a computationally intensive puzzle, analogous to melting a glacier, which consumes significant computational resources and energy, thereby deterring malicious activity.