The flight bans came amid fears that the ash - a mixture of glass, sand and rock particles - can seriously damage aircraft engines.

BBC: EU emergency talks called on volcanic ash air chaos

But perhaps more importantly, there is the huge reputational damage for a bank that used to be seen as a rock of probity and stability.

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"The removal of the graffiti may well damage some of the very small, fine, holds that exist on the boulders and on the rock", Dave Gibson explains.

BBC: Glasgow & West Scotland