1. Large basins allowing the input of ore-bearing solutions and hampering the reflux of brines (see bar theories)
2. the appropriate facies relation of host and source rocks (changing redox regimes)
3. a good supergene source at the rim of the basin
4. a good hypogene source syngenetic to deposition underneath
5. deep-seated fractures as pathway for the ascending metaliferous solutions
6. intraformational reworking and redeposition to upgrade the ore mechanically or chemically
7. A good sealing sedimentary blanket and a helpful (fault)structural reime to join its other and protect the ore mineralization from being destructed or diluted