South Africa’s longest mining strike is nearing an end as workers and representatives of the Association of Mineworkers and Construction Union (AMCU) are urging their leader Joseph Mathunjwa to sign an agreement with three major platinum firms, which have announced “in principle” agreements. Together, the companies represent 40% of global output.

The deadlock has not officially ended, but shows signs of breaking amid rallies with thousands of cheering, stick-carrying miners as the miners—Anglo American Platinum, Impala Platinum and Lonmin plc—announced “in principle undertakings” with leaders. The companies pledged a final deal in the coming days; 70,000 workers have been on strike since January, causing output to fall at its fastest in 50 years.

The monthly $93 offer totals a 20% pay hike, but represents a fraction of the 150% the union first demanded, sending sub-Saharan Africa’s No. 1 economy into a tailspin. A website by the companies said the strike has cost them $2.05 billion in revenue; South Africa hosts 80% of the world’s reserves of the precious metal.

“The principles that underpin the proposals seek a sustainable future for the three companies for benefit of all stakeholders and to afford employees the best increase under current financial circumstances,” the U.K.-based Lonmin, the smallest of the three; details were undisclosed to stock exchanges in Johannesburg and London.