East Asian coal briquettes

Korea Introduced to Korea from Japan in the 1920s, rose in popularity following the Korean War. By 1988, 78% of South Korean households used , but this fell to 33% by 1993 as people switched to oil and gas boilers, and was estimated to be used by just 2% of households by 2001. Earlier briquettes used to have 9 holes. Later on, 19 holes used to be most common, but nowadays 22 holes is most common. A number of suicides in South Korea have seen the use of for carbon monoxide poisoning. File:19-hole yeontan briquette making tools.jpg|19-hole yeontan template and yeontan (9-hole yeontan visible in corner) File:22-hole_yeontan_briquette.jpg|22-hole yeontan in use File:31-hole yeontan briquette.jpg|31-hole yeontan ==See also==