  Spectra of extranuclear clouds within the ionization cone of Circinus galaxy
are presented and modelled assuming photoionization by the Seyfert 2 nucleus
but no preconceived assumption concerning the spectral shape of the ionizing
AGN radiation or the gas density distribution.
  The most important result is that, regardless of the assumed AGN spectral
shape or density distribution, the metal abundances are remarkably well (+/-0.2
dex) constrained by the data. Oxygen and neon are found to be a factor of 5
below solar, while nitrogen is solar. The large N/O overabundance is in
agreement with the chemical enrichment expected from the old (circum)nuclear
starburst. Similar studies of extranuclear clouds in other objects could
therefore provide a powerful tool to determine metallicities and trace past
starburst activity in AGNs.
  Other implications such as the role of shock excitation, which is effectively
excluded, and the intrinsic shape of the AGN ionizing continuum, which is
poorly constrained by the data, are also discussed.
