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Tier 0: Resources produced from harvested sunlight (Energy Cells; ECs), asteroids (minerals and water) and nebulae (gases).
Tier 1: Basic foods produced by the main factions from ECs and Water (Tier 0 Wares).
Tier 2: Food and drugs produced from Tier 1 Wares, Water and ECs.
Tier 3: Refined Wares produced from harvested minerals, gases and ECs.
Tier 4: Advanced Wares produced from Tier 3 Wares and ECs.
Tier 5: Components produced from Tier 3, Tier 4 and, occasionally, other Tier 5 Wares.
Tier 6: Equipment, including ship hulls, ship equipment and station modules
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