As America’s first female secretary of state, she was known as a tough bargainer who brooked no nonsense as she travelled the world, facing down despots such as Saddam Hussein and Kim Jong-il. But Madeleine Albright has revealed that she had an unexpected diplomatic tool — costume jewellery.

She began using brooches in 1994 after the Gulf war when the Iraqi press referred to her as “an unparalleled serpent”. Then US ambassador to the United Nations, she responded by wearing a golden brooch depicting a coiled snake to her next meeting with the Iraqis.

“I didn’t consider the gesture a big deal,” she writes in a new book, Read My Pins, adding: “I doubted that the Iraqis even made the connection ... As the television cameras zoomed in on the brooch, I smiled and said that it was just my way of sending a message . . .

“I thought, well, this is fun. So then I went out and I bought a bunch of costume jewellery to signal what my mood of the day was.”

When she became President Bill Clinton’s secretary of state in 1997 she acquired more and more, giving new meaning to the term “statement jewellery”.

There were crabs and turtles to indicate her frustrations at the slow pace of talks in the Middle East. In preparation for one meeting with Yasser Arafat, she placed a large wasp in a prominent position on her jacket. The Palestinian leader was visibly perturbed.

“I wore wasps on days that I wanted to do a little stinging and deliver a tough message,” she explained.

While the first President George Bush had been known for saying, “Read my lips”, Albright urged colleagues to “Read my pins”.

The signals were soon being recognised by foreign leaders such as Vladimir Putin, who told Clinton he could tell what the mood of a meeting would be by glancing at Albright’s left lapel.

Some of her best pieces were kept for the Russians. To make clear her views on their refusal to acknowledge atrocities in Chechnya, she chose a particular favourite for a summit with Putin: “I wore the three monkeys — the Hear no Evil, See no Evil, Speak no Evil monkeys — which was that they were not seeing what was going on in Chechnya . . .”

When Albright and Igor Ivanov, the Russian foreign minister, negotiated an anti-ballistics treaty, she selected a 4in interceptor missile.

“The best, I think, was the Russians had actually bugged the State Department at a certain period. We discovered that there was a bug in one of our conference rooms, so the next time I met the Russians I wore this huge bug pin. So they got it.”

It was not all bad news. There were balloons, butterflies and flower brooches for when she felt negotiations were going smoothly.

“I had great sun pins,” she recalls. “And I wore a sun, actually, to South Korea because President Kim Dae-jung had a policy called ‘the sunshine policy’, which was his way of saying that there ought to be better contacts with North Korea.”

The 72-year-old Albright, who is often mistaken for Margaret Thatcher, has amassed a collection of 300 brooches which have gone on display at the Museum of Arts and Design in New York. Some were gifts, including a lion presented to her by Robin Cook, Labour’s late foreign secretary. The technique of using a brooch to send a message was adopted by Hazel Blears, the former Labour minister, when she resigned from the cabinet in June. On her lapel was a badge depicting a sinking ship over the words “rock the boat”.

Yet in Albright’s case a brooch almost got her cabinet career off to an embarrassing start. She had chosen a special eagle for her swearing-in ceremony but, just as she began to take the oath, it came unclasped. The official photographs show it hanging off.

“I have one hand on the Bible and one hand in the air and the eagle was swinging around in the breeze,” she recalled.

Times recommends

• Tewkesbury: when the memories flood back
• How I lost the gift of joy for a while
• The A-Z of winter style rules