It is said there are many shades of the colour grey - at least 50 according to a certain work of literature.
However, one building's particular hue has been deemed unfit by a city council, which is taking measures to change it.
Enforcement action has been taken against a Norwich hair salon, after designers painted it the wrong shade of the colour.
StandenMay salon, on Magdalen Street, is in a listed building and at the beginning of 2017 was painted dark grey, as the new business moved in.
However, the shade of paint used was not one of the 33 shades approved for facades of listed buildings, or the 34 permitted for joinery - as set out by Norwich City Council.
In December, the owners were given permission to repaint the exterior in an off-white, however with the building still grey, the city council has taken action to move the process along.
Ellie Denny, the salon's manager, said the situation had been 'extremely frustrating' for the business.
She said: 'The planning application itself took three or four days of my time and when we received approval we were told we had three years to get the work done.
'We're still a new business and it is going to be costly for us to do, so we budgeted to do it next summer - then we received the enforcement notice.'
Miss Denny said the re-painting the building will cost between £4,000 and £5,000.
She added: 'We feel a bit picked on to be honest - there is a real community feel in this area and none of our neighbours have had any problem. Some of them are even painted the same colour.
'Surely there are more important things the council could be doing than chasing us over this? We feel very unsupported as a small business.'
However, a spokesman for Norwich City Council said: 'We only ever take any form of enforcement action as a last resort.
'Officers have been in regular contact with the applicant through this issue and in particular about when the work needed to be carried out, because of its listed building status.
'We very much look forward to there being a successful outcome.'
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here