A South African court on Monday began two weeks of hearings to determine if gold miners suffering from debilitating lung diseases they say they contracted at work can proceed with a class action lawsuit against the industry.

The stakes are high with miners seeking damages that could amount to billions of rand at a time when South Africa's gold industry is in a state of steep decline in the face of depressed prices and soaring costs.

The industry is opposed to the lawsuit proceeding as a class action, which would enable plaintiffs to join forces as a "class" as opposed to thousands of individual cases.

Plaintiffs, many from neighbouring countries such as Lesotho, are suing for compensation on the grounds that they contracted silicosis and tuberculosis through neglect.

Working deep underground for years without proper protection, countless South African miners inhaled silica dust from gold-bearing rocks and later contracted silicosis.

A disease which causes shortness of breath, a persistent cough and chest pains, it makes people highly susceptible to tuberculosis, which kills.

"If the court cer­ti­fies the class, the law­suit will pro­ceed as the largest ever class action law­suit in the coun­try and on the con­ti­nent," the Legal Resources Centre, a human rights group which has joined the case, said in a statement on Monday.

The planned suit, which has little precedent in South African law, has its roots in a landmark ruling by the Constitutional Court in 2011 that for the first time allowed lung-diseased miners to sue their employers for damages.

Attorney Richard Spoor, whose legal battle against a South African asbestos-mining company led to a $100-million settlement in 2003, told Reuters he had signed up more than 30 000 former miners and their dependants for the lawsuit.

Spoor would not be drawn on the specific amount he expects his clients to extract from the industry but said "we are certainly talking billions of rand."

Another law firm, Abra­hams Kiewitz, has also joined the suit, which targets AngloGold Ashanti, Harmony Gold, Sibanye Gold, Gold Fields, Anglo American, DRDGold, and African Rainbow Minerals.

Industry officials would not comment on the case and the ruling on whether it can proceed as a class action may not be made until next year.