Camilla also went on something of a spending spree in Morocco on the last day of her visit with the Prince of Wales.
As Charles met religious leaders, his wife toured the busy medina in the historic city of Fez.
Camilla stopped for lunch at the popular Cafe Clock and was given a tour by British owner Mike Richardson.
Arriving at a table where a henna artist was working, the Duchess sat down.
"Ah," she said, rather nervously, after being told by artist Mina Amori, 32, that the tattoo can last up to two weeks.
But the Duchess shrugged her shoulder and held out her right index finger.
She sat smiling as the design of an orange water flower in the traditional Fez regional style was painted on in a matter of minutes.
"This will look good at the wedding," she said later with a giggle to a reporter.
The tattoo should be gone before Prince William marries Kate Middleton at Westminster Abbey in 23 days' time.
The press Association