At least 18 bodies were pulled out on Thursday after the gas explosion in northwestern Antioquia province. Rescuers had little hope for 53 others caught 6,500 feet (2,000 meters) below the surface as families buried some of their dead.
Rescue efforts were suspended several times while workers ventilate the mine shafts to disperse dangerous gases.
"We believe there were between 70 to 72 people inside, and we've recovered 18 bodies so far," said Luis Alfredo Ramos, governor of Antioquia province. "The rescue operation is still suspended because of an accumulation of gas and they are in the process of ventilation."
The blast at the San Fernando mine occurred far from the major operations run by companies such as Drummond and Glencore in the world's No. 5 coal exporter, which is enjoying a boom in mining and energy investment.
The explosion will not have a broad impact on the coal market because the mine is small and supplies the domestic market and some European traders, market sources said.
Some still hoped to find their missing relatives alive.
"People are holding on to every hope of finding them alive," said Juan Velasquez, a 22-year-old farmworker whose father-in-law worked at the mine. "Authorities say that there is no chance of finding survivors, but we can't lose hope."
Hundreds of people, some sobbing, others silent, attended an outdoor funeral for nine of the dead miners in Amaga, a poor rural town ringed by coffee plantations and coal mines, where dozens of miners have been killed over the years.
Other families gathered at a nearby sports hall where authorities set up a makeshift morgue and bodies wrapped in white sheets were put in hearses. Many carried photographs of missing relatives.
Coal mining is dangerous even in more developed countries. Explosions and collapses are common, especially in China. In April, an explosion killed 29 miners in West Virginia in the deadliest US mine disaster in more than 20 years.
The disaster will put the spotlight on mining safety regulations in Colombia, where the industry ranges from large deposits operated by multinationals to hundreds of small, makeshift pits that produce coal for local markets.
Colombian authorities said they would investigate the cause of the blast before deciding on any action.
The South American country produces about 70 million tons of coal a year, with most of its exports shipped to Europe, the United States and the Caribbean but with increasing focus on Asian countries such as China.
The San Fernando mine produces 240,000 tons a year of thermal coal, according to mine and energy officials.
Last year, a methane gas explosion in another Antioquia province coal mine killed eight workers and, an explosion in Norte de Santander in 2007 killed 31 miners.
Colombia has benefited from the boom in energy and mining investment under President Alvaro Uribe, who sent troops out to drive back leftist rebels fighting Latin America's oldest insurgency that once controlled large parts of the country.
Uribe steps down in August and his former defense minister, Juan Manuel Santos, is favored to succeed him in a runoff on Sunday. Presidential candidates have debated how to handle the influx of mining and oil dollars.
