1 October 1986
Following the Kinross mine disaster killing 177 miners (all migrant workers), fellow mine workers held memorial services throughout the mining industry to mourn these deaths, under the supervision of NUM (National Union of Mineworkers). An earlier memorial service, sponsored by the mine owner, Gencor co., was disrupted by workers who protested the mine’s safety standards & rejected the company-sponsored memorial in favour of their own, scheduled for 1st October.  Workers had also objected to the exclusion of union leaders from the company-sponsored memorial service guest list, further supporting the call for the worker-led memorial services & Day of Mourning. The cause of the deaths had been attributed to poisonous gases that had accumulated in their working stopes. The toxic gases were the result of an accidental fire which spread through the mine, burning through plastic wire coverings & polyeurethane wall coatings. The day of mourning was observed by thousands of workers from different mines who were allowed to observe 5 minutes of silence by the mine's management. COSATU (Congress of South African Trade Unions) supported the call for the 1st October Day of Mourning.   Further reading: Online BBC news article on the Kinross mine disaster. Online Philadelphia Inquirer news article on the rejection by mineworkers of the corporate-sponsored memorial for the Kinross mine disaster. Online The Guardian news article on the Kinross mine disaster. Personal recollection of the Kinross Mine Disaster by Mbhobana Elliot Mhlabeni. Numsa Health & Safety Address remembering the Kinross Mine Disaster    
References

Van Niekerk, P. (1986). "Gencor agrees to NUM day of mourning ", Weekly Mail: Vol. 2. No 38., p.7

Time Magazine (1986). "South Africa Disaster in a Gold Mine", Vol. 128. No 13