Tennessee's commemorative quarter was unveiled yesterday in a toe-tappin,' hand-clappin' ceremony that even had Treasurer of the United States Rosario Marin keeping time with the songs of Isaac Hayes, Ricky Skaggs, Marty Stuart and Ruby Wilson.

The program at the Country Music Hall of Fame was dedicated to a 25-cent coin, but it was no two-bit affair.

Tennessee's quarter will circulate for 10 straight weeks, then never be re-minted. In 10 years, all 50 states will have quarters introduced in the order in which they joined the Union. Tennessee is the 16th state.

''While they are collector's items, they will spend with the best of them -- so use them!'' Marin advised more than 225 state and local dignitaries.

The ''Musical Heritage'' coin features a trumpet for the Memphis blues, a guitar for the Nashville sound and a fiddle for East Tennessee folk songs. It also has three stars for the state's Grand Divisions and was conceived by Shawn Stookey, an elementary school teacher in New Johnsonville, Tenn.

The audience was mesmerized by Skaggs' chilling a cappella version of "Amazing Grace."

''I don't know about you, but I had goose bumps on my back,'' Sundquist said. ''When I sing it in the shower, it doesn't sound nearly that good.''

Hayes' subterranean voice had the crowd on its feet for "God Bless America" and Wilson, called the Queen of Beale Street, had it cheering for a soulful "Tennessee Waltz."

Skaggs, on a mandolin, and Stuart, playing Mother Maybelle Carter's guitar, closed the hour and 20-minute ceremony as they led the audience in "Will The Circle Be Unbroken," a hallmark of the famed country Carter Family.

By Jim East