Joni Mitchell, one of the few popular artists around today who can, without hyperbole, be termed an original. Her style is quicksilver, her moods well-defined, her vocal abilities, including more than a three octave range, astounding, and her performance dazzling.

The Woodstock generation has grown old. That is what we have been told in recent weeks as the nations media covered the tenth anniversary of the mammoth upstate New York concert that rocked the nation.

Media reports that many of the acts that headlined the three days of love in 1969 are not even around anymore  victims of the alarming rock and roll attrition rate, drug overdoses and vast changes in musical tastes over the intervening decade  have been hashed and rehashed.

On a cool breezy Tuesday night at Blossom Music Center, though, the generation showed up once again, to carry on a public love affair with a woman who, a survivor of the 1969 show, has done more than most to etch Woodstock in our memories, Joni Mitchell.

After a several-year absence from Cleveland area stages, Motchell seemed delighted with the Blossom turnout and proceeded to pay tribute with a long moody and masterful set of current and older tunes.

ON THE EVE of the tenth anniversary of Woodstock, Mitchell wowed her followers to a sometimes magical, always mesmerizing tour de force of music, utilizing both her early folky stance and her new interest in jazz.

Mitchell is one of the few poular artists around today who can, without hyperbole, be termed an original. Her style is quicksilver, her moods well defined, her vocal abilities, including more than a three octave range, astounding, and her performance dazzling.

She has emerged from her shell with this tour. In the old days she would seem nervous on stage, but at Blossom, she was Svengali, and the audience her willing subjects.

Dressed in a dark tunic caught casually in the middle with a glittery belt, her now-curly hair falling alluringly over one eye, she seemed a bright and welcome contrast to the dark moods of some of her songs.

BACKED BY A four-piece band and the astounding sax breaks of Michael Brecker, she led the audience through a steady progression that visited all of the stages of her career.

No doubt yielding to the wishes of the audience, she opened with a handful of older songs, the familiar churning Big Yellow Taxi leading the way, followed by several other tunes from her 1974 Court and Spark album.

Then came a progression of tunes (Coyote, from Hissing of Summer Lawns) leading to material from her new Mingus LP.

Fittingly enough it was Court and Spark that launched her interest in jazz (she did the tongue-in-cheek Lambert, Hendricks and Ross tune Twisted) which has culminated in the release of Mingus, a tribute to the late seminal jazzman Charles Mingus, who died while working on the album with her.

IT IS INDICITIVE of her new-found ease on stage that she abandoned it to her session players, who, pleased with estended solos, accentuated when she returned to do duets with them.

After these breaks, Mitchell surged into the jazz from Mingus with Beale Street, a pean to the early greats of the art form leading the way. It is during Beale Street that she invokes the name of W.C. Handy, the legendary Memphis musician who started jazzs trip up the Mississippi River from New Orleans.

The Mingus material showed the massive influence of the wealth of jazz singers who precede Mitchell. The melodies are backed by shuffling rhythms wandering and flitting from place to place within the music.

After God Must be a Boogeyman from MIngus, Mitchell thrilled the crowd with one of the tunes they had come to hear.

EVEN BEFORE the beginning strains of Free Man in Paris, which, while it cynically speaks of stoking the star-maker machinery behind the popular song, remains her greatest commercial success, the crowd was on its feet cheering.

Raised on Robbery (also from Court and Spark) also sent the audiences lust for more familiar older music into overtime, with the Blossom version every bit as sinewy as the original.

Changing the mood once again to finish the show, Mitchell called on the Persuasions, the legendary Phliedelphia a capella soul group currently opening for her, onstage for a dip into the music of the 50s with Why Do Fools Fall in Love? and, though diametrically opposed in nature to the cool jazz of Mingus, the music seemed to blend well into a potpourri of harmony.

Leaving the stage in triumph, Mitchell returned alone, ast at the paiano and reached back in her memory for the tender Richard, from the Blue LP. Her stark presence alone on the stage was a magical background for the songs plaintive wandering story of erstwhile love.

JONI MITCHELLS songs are above all, personal. More than any other artist currently performing, she succeeds in blending the bittersweet disappointments of lost love with a sometimes wacky set of characters. They reflect the paradoxical joys and sorrows of life.

Perhaps out of sentimentality, and perhaps to make a statement, Mitchell answered the crowds cries for a second encore with her best known (and often covered) tune  Woodstock.

Though the crowd went crazy for the familiar warning &And we have to get ourselves back to the Garden, she did the song with a softened, almost plaintive tone, as if calling up for the audience the ghosts of the great festival and lamenting their all-but-forgotten idealism.

It was half-way through the song that she made her only sally into her former political style by altering the lyrics to make brief reference to the nation being caught up in political games, and then walking off the stage to play the final chords out of sight backstage, as if, perhaps, as a haunting reminder of days gone by.