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Eclipsing of the X-ray emitting region in active galactic nuclei (AGN) is apotentially powerful probe to examine the AGN environment and absorberproperties. Here we study the eclipse data from the 2016 XMM-Newton observationof NGC 6814 using a colour-colour analysis. Colours (i.e. hardness ratios) canprovide the advantage of better time-resolution over spectral analysis alone.Colour-colour grids are constructed to examine the effects of differentparameters on the observed spectral variability during the eclipse. Consistentwith previous spectral analysis, the variations are dominated by changes in thecolumn density and covering fraction of the absorber. However, during maximumeclipse the behaviour of the absorber changes. Just after ingress, the eclipseis described by changes in column density and covering fraction, but prior toegress, the variations are dominated by changes in column density alone.Simulations are carried out to consider possible absorber geometries that mightproduce this behaviour. The behaviour is inconsistent with a single,homogeneous cloud, but simulations suggest that multiple clouds, perhapsembedded in a highly ionised halo, could reproduce the results. In addition, wedetermine the orbital covering factor (fraction of orbital path-length) basedon evidence of several eclipses in the 2016, 64-day Swift light curve. Weestimate that ~ 2-4 per cent of the orbit is covered by obscuring clouds andthat the distribution of clouds is not isotropic.

A Colourful Analysis: Probing the Eclipse of the Black Hole and Central Engine in NGC 6814 Using X-ray Colour-Colour Grids