Ground based in situ observations of filter_3pack at Amberd (AM0001R). These measurements are gathered as a part of the following projects EMEP and they are stored in the EBAS database (http://ebas.nilu.no/). Parameters measured are: calcium in aerosol (mass_concentration_of_calcium_in_dry_aerosol_particles_in _air), magnesium in aerosol (mass_concentration_of_magnesium_in_dry_aerosol_particles_in _air)