  If axions or axion-like particles exist and are detected, they will not only
extend the standard model of particle physics but will also open a new way to
probe their sources. Axion helioscopes aim to detect axions which are produced
in the core of the sun. Their spectrum contains information about the solar
interior and could in principle help to solve the conflict between high and low
metallicity solar models. Using the planned International Axion Observatory
(IAXO) as an example, we show that helioscopes could measure the strength of
characteristic emission peaks caused by the presence of heavier elements with
good precision. In order to determine unambiguously the elemental abundances
from this information, an improved modelling of the states of atoms inside the
solar plasma is required.
