ITS unpopularity hasn't stopped United States legislators pressing on with plans to mint a new version.

Q: Something to do with Sacagawea?

A: On the contrary;

she's a heroine in the US, especially among native Americans.

Q: Why?

A: She was the only woman to accompany the explorers Lewis and Clark on their epic journey to find a westward passage across America to the Pacific. They might not have succeeded if it hadn't been for Sacagawea.

Q: Who was she?

A: A Shoshone captured by the Minnetarre tribe as a child. She was gambled away in 1804 to a French Canadian named Toussaint Charbonneau whose wife she became. Lewis and Clark met her when they reached the Dakotas.

She and Charbonneau helped the party reach the west coast. Her son, Baptiste, was born on the way. The family returned to the Minnetarre country.

Sacagawea died in the Shoshone Agency around 1884, aged about 100.

Q: Her endeavours recognised by a coin?

A: The gold-coloured dollar coin (worth about 52p), imprinted with an image of her face, was issued in 2000 - but not simply to honour her achievements.

Q: Oh? A: The Treasury saw the initiative as a winner in the campaign to encourage Americans to use more dollar coins and fewer dollar bills. Paper bills last less than two years. Coins have a lifespan of some 23 years. If coins became more popular there'd be a big cash saving for the government.

Q: But they're not jingling in American pockets?

A: A recent survey found that 97% of Americans hadn't used a dollar coin for a month, while 74% couldn't remember ever using one. The latest plan to boost their use involves minting dollar coins bearing the faces of US presidents. Just don't watch their lips.