The Georgian Period of 1890s Britain were sometimes referred to as the "Mauve Decade," because of the popularity of that purplish-pink colour. Hitherto that time, purple dye was only attainable from a certain rare shellfish, so the dye was very expensive. That is why it became the colour of the robes of royalty. William Henry Perkin invented one of the first synthetic dyes, made of aniline, in the colour that came to be called mauve. This allowed the widespread use of the colour in fashion, and wearing it became all the rage. Mauve became associated with daring and flaunting of social norms, specifically with decadent art and homosexuality. (By the 1950s, lavender came to symbolize homosexuality, then pink, beginning in the 1970s.) Well-known figures in the art world during The Mauve Decade were gay, such as author Oscar Wilde and artist Aubrey Beardsley. The latter's sexually explicit prints and engraving shocked the artistic establishment. The sensuous genre known as Art Nouveau flourished during this period. Louis Comfort Tiffany's stained-glass lamps and Henri Lartigue's jewellery, which incorporated images of the natural world, were popular. "The Mauve Decade" was the title of a 1926 book by Thomas Beer book about the "Gay Nineties" in the United States, which paralleled the British movement's flaunting of authority and social mores. Beer believed the country was moving away from its New England traditions to a time of "decay and meaningless phrases," He took the book's title from a quote from U.S. Artist and ex-patriate to England James Whistler, who said, "Mauve is just pink trying to be purple."