The RMI, compiled by the Switzerland-based Responsible Mining Foundation, said while a few companies were strengthening equality and gender diversity practices, too many were not paying attention to basic issues, such as providing female workers with fit-for-purpose safety equipment.

The research revealed that most of the 30 large-cap companies assessed show little or no evidence of efforts to strengthen the gender balance of their leadership and governance teams.

The companies scored an average of only 4.5% on the question of implementing interventions to bolster the diversity and inclusivity of their board and senior management.

It seems there is more to do at the lower end of the workforce.

It is estimated women account for about 10% of jobs in the large-scale mining sector.

"It is at the mine-site level where women are most vulnerable to unsafe and hostile working conditions," the RMI said.

"Basic requirements, such as fit-for-purpose goggles, helmets and other personal protective equipment (PPE), or secure toilet and changing room facilities, are often lacking for women workers.

"The dimly lit and confined environment of underground mines makes them particularly unsafe for women, with the heightened risk of gender-based harassment and violence."

A 2014 study by Canada's Mining Industry Human Resources Council found that nearly 40% of women working on mine sites reported having experienced harassment in the last five years.

The RMI's analysis showed that over 75% of the companies assessed were unable to demonstrate that they have systems in place to ensure the provision of gender-appropriate PPE for their women workers.

While many have policies in place to prevent sexual harassment, three quarters of the companies showed no evidence of systematic measures to prevent harassment of women workers.

The RMI noted countries could prohibit discriminatory labour practices and set requirements for female employment.

South Africa and Chile are cited as examples, as they have policy measures in place for female workers.

The RMI said international initiatives, such as the Women's Rights and Mining group or the UN Working Group on Business and Human Rights, as well as unions, could help to raise global awareness of gender issues in mining and work to improve policies and practices.

Three Australia-based companies were analysed by the RMI: BHP, Newcrest Mining and MMG, while others to have operations in Australia include Rio Tinto, AngloGold Ashanti, Gold Fields, Newmont Mining, Barrick Gold, Anglo American, Glencore and Zijin Mining.