Queen's seal of approval boosts the meek and mighty Royal print: Austen Kopley of Barnard & Westwood In the back streets of London's Clerkenwell, a small print shop is preparing for a show fit for a queen. Barnard & Westwood has been printer to Queen Elizabeth II since 1984. As she celebrates the 60th anniversary of her coronation this week, holders of royal warrants such as this are preparing to tout their wares at the Coronation Festival, a three-day trade fair in the grounds of Buckingham Palace next month. The Last Word Gold ink oozes down the side of the printing machines, which made the programmes for Tuesday's coronation anniversary service, the marriage of the Duke and Duchess of Cambridge and Margaret Thatcher's funeral. It recently received a second royal seal of approval, from the Prince of Wales. Austen Kopley, owner-manager, says he applied for another spirally crest that warrant holders are entitled to display because the first was so effective at setting his business apart. It is the prestige and it proves good quality and value. The printer boasts an elite clientele from auction house Sotheby's to drinks group Moët Hennessy, and is pursuing other markets by opening an online store. Its royal connection has attracted a Japanese fashion house. But like all royal warrant holders, Mr Kopley must be careful about disclosing the royal shopping habits. Companies speak in fear of the Lord Chamberlain book, a set of rules composed by the senior official of the royal household, which they must follow or risk losing their warrant. For centuries the crests have been a discreet way of proving a product's establishment credentials, adorning products and services that have been used by the royal household for at least five years. Elizabeth I granted warrants to her suppliers in the 16th century. Now the crest appears on everything from televisions to tea bags. Richard Peck, secretary of the Royal Warrant Holders Association, says the badges help exporters win business on the back of the royal family's global brand. The family have long appealed to other nationalities and have received a further boost since the diamond jubilee last year. "If you go into export markets . . . the royal warrant represents a symbol of quality and excellence," he says. A huge amount of due diligence is done on these businesses, so you get a really good feel about who will perform through thick and thin. More than 200 warrant holders will exhibit their products and services to the 60,000 visitors, including foreign trade delegations, who are expected to attend the fair. While luxury goods companies such as Burberry have made much of their British heritage, the warrant holders range from the traditional to the high-tech, from small traders to multinationals such as GlaxoSmithKline, Jaguar Land Rover and Bentley. The latter three are also the sponsors of three galas at the event. Samsung has a royal warrant providing electronic equipment, there are a number of software companies and an engineering firm which provides fruit-picking machinery. But then at the other end of the spectrum you also have a carriage maker," Mr Peck says. Roger Pope, optician to the Queen, displays a royal crest over the door of his shop near London's Harley Street. "We can't make it a main feature of the business," he says. There are lots of rules on what you can and can't do. Mr Pope's offerings include frames made of gold or buffalo horn, or dolled up with diamonds. As shoppers from emerging markets flock to London, he has more wealthy overseas clients, and some ask for glasses like the Queen's. Mindful of the Lord Chamberlain, Mr Pope toes the line: "I won't say the specific frame, but I can give an idea of the style."