In the 1950s mining rights for the pyrochlore deposit in Araxá were conceded to both CBMM and the government of the state of Minas Gerais.
Since then a partnership developed between CBMM and state-owned Camig (now Codemig) that in 1972, at Camig's request, transformed into an association aimed at the joint exploration of the pyrochlore ore from the mines conceded to CBMM and to Codemig.
The association established for this new phase resulted in the constitution of a corporation and a profit sharing account (sociedade em conta de participação - SCP). This association is registered in the form of a public instrument (escritura pública).
Camig (now Codemig) and CBMM formed a corporation, Comipa (Companhia Mineradora do Pirocloro de Araxá), that they jointly manage and for which unanimity is required for corporate decisions. The two companies leased their mining rights for 60 years to Comipa, which in turn mines the pyrochlore ore in equal parts from each company's deposit and sells the ore exclusively to the SCP (at cost plus 5% profit margin) for beneficiation, manufacturing (there are more than 15 processing steps involved to arrive at a marketable final product) and marketing.
In accordance with the association, Codemig receives 25% of the corporation's net profit (including the sale of products resulting from CBMM's mining rights and earnings from subsidiaries that were later constituted by CBMM).
The agreement between CBMM and Camig (now Codemig) was approved by the state governor and was signed for a period of 60 years.