Living organisms acquire a characteristic minor fraction of 'radiocarbon' by equilibrating with the carbon dioxide of ambient air or surrounding waters.

Dark Age people might possibly have been burning very old wood, if they'd found it in a bog, and in that case 'radiocarbon' would date the growth of the tree, not the time if its burning.

Also contamination of an object with more recent 'radiocarbon' , leading to an inaccurate date, is always a threat and difficult to detect.

Some of these neutrons react with nitrogen atoms in air, converting them into a radioactive isotope of carbon: carbon - 14 or 'radiocarbon' , with eight neutrons in each nucleus.

These data were compared with the distribution of 'radiocarbon' in free glucose and fructose isolated from the same sample.