Highly combustible materials that leave little residue, such as wood or coal, were thought to be made mostly of phlogiston; non-combustible substances that corrode, such as iron, contained very little.
Os materiais altamente combustibles que deixan pouco residuo, como a madeira ou o carbón, críanse feitos na súa maior parte por floxisto, mentres as substancias non combustibles que se corroen, como o ferro, conteñen moi pouco.