Analysis of iron in organic materials: an unrecognized problem of volatility

Summary All commonly used techniques of wet and dry ashing biological materials have proved unsatisfactory for iron analysis. High variability between replicates is attributable to the loss of iron in volatile form, almost certainly as the pentacarbonyl. A low temperature digestion is suggested as an improved technique. Generation of volatile iron compounds in vegetation fires may contribute to biogeochemical cycling of iron.