[en] Atomic absorption spectroscopy (AAS) was found to be a suitable method for the estimation of iron, copper, zinc, magnesium, aluminium and lead in urinary calculi: graphite furnace electrothermal atomization was required for lead and flame atomization for the others. A standard urinary stone solution was made up and calibrated for each element using the method of standard additions. In all case, absorption varied linearly with concentration; reproducibility, accuracy and recovery were satisfactory for all elements. Conventional atomic absorption standards in 1% nitric acid solution had low apparent values as a percentage of the true values would be: Fe, 108.5; Cu, 103.1; Zn, 106.4; Mg, 125.0; Al, 103.6; Pb, 102.2%. Also, apparent concentrations of magnesium, zinc and copper in dilute nitric acid solution varied significantly with acid strength. It was concluded that in order to minimise matrix and Ph effects, urinary stone analysis should be done against the standard urinary stone solution. (author)