In Chile it is called the contract law miner (A typical contract mining ) whereby a part "Aviator " It undertakes to give or do something for the mine owner of a mining membership, in Exchange for paid with proceeds of the mine or a share of this. It is an onerous contract ( because both parties seek to gain ) random because the gain of the flier is uncertain and depends on product enough to pay for mine and therefore, has a choice of payment, and it is nominated, because this is defined and regulated in the Chilean mining code.
