The decision was made in light of a possible failure of five dams at both complexes, which are located in Minas Gerais, the same state where the Feijão mine dam collapsed last month.
A syndicate of underwriters, co-led by GMP Securities and BMO Capital Markets, had agreed on a bought deal basis to buy 7.5 million shares at C$5.40 each.
The companies envision an investment from Glencore that will help fund construction in exchange for offtake of production of four million tonnes of iron ore a year.